Draft BAR and EMPr - · PDF fileDraft BAR and EMPr: Construction of a Package Sewage Treatment...

KWAZULU-NATAL: Fairway Green, 3 Abrey Road, Kloof, DURBAN | PO Box 2221, Everton 3625 Tel: +27 31 764 6449 | Fax: +27 31 764 4907

65/67 Davenport Centre, 89 Helen Joseph Rd, Glenwood, DURBAN

Tel: +27 31 827 6426

WESTERN CAPE : The Southern Right, Streenbras Street, Brenton on Sea, KNYSNA | PO Box 2984, Knysna 6570 Tel: +27 44 381 0712 | Fax: +27 86 569 5554

SOUTH AFRICA

[email protected] | www.futureworks.co.za

Draft BAR and EMPr:

Construction of a Package Sewage Treatment

Plant, Sewerage and Stormwater Infrastructure within a Sensitive Natural

Environment at Crowhurst Estate

(DM/0066/2013)

2

AUTHOR & QUALITY CONTROL INFORMATION: Report Authors: Nicci Diederichs Mander (CEAPSA; Pr Sci Nat) and Michael Van Niekerk (CEAPSA) Report Release Date: Draft Report for comment: 28 March 2014

Final Draft Report to DAEA: Final Report:

KZN CAPE REGION PO Box 2221, Everton, 3625 PO Box 2984, Knysna, 6570 Gardenia House, Fairway Green, Southern Right, 632 Steenbras Street, Knysna 3 Abrey Road, Kloof Tel: 031 764 6449, Fax: 031 764 4907 Tel: 044 381 0712, Fax: 086 569 5554

Basic Assessment Report

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GIBELA UMKHUMBI OLWA NOBUBHA

(For official use only)EIA File Reference Number: DC/NEAS Reference Number: KZN/EIA/Waste Management Licence Number: (if applicable)Date Received:

BASIC ASSESSMENT REPORT

Submitted in terms of the Environmental Impact Assessment Regulations, 2010promulgated in terms of the National Environmental Management Act, 1998 (Act No. 107 of 1998)

This template may be used for the following applications:• Environmental Authorization subject to basic assessment for an activity that is listed in Listing Notices

1or 3, 2010 (Government Notices No. R 544 or No. R 546 dated 18 June 2010); or• Waste Management Licence for an activity that is listed in terms of section 20(b) of the National

Environmental Management: Waste Act, 2008 (Act No. 59 of 2008) for which a basic assessment process as stipulated in the EIA Regulations must be conducted as part of the application (refer to the schedule of waste management activities in Category A of Government Notice No. 718 dated 03 July 2009).

Kindly note that:

1. This basic assessment report meets the requirements of the EIA Regulations, 2010 and is meant to streamline applications. This report is the format prescribed by the KZN Department of Agriculture &Environmental Affairs. Please make sure that this is the latest version.

2. The report must be typed within the spaces provided in the form. The size of the spaces provided is not indicative of the amount of information to be provided. The report is in the form of a table that can extend itself as each space is filled with text.

3. Where required, place a cross in the box you select.4. An incomplete report will be returned to the applicant for revision.5. The use of not applicable in the report must be done with circumspection because if it is used in respect of

material information that is required by the competent authority for assessing the application, it will result in the rejection of the application as provided for in the regulations.

6. No faxed or e-mailed reports will be accepted.7. The report must be compiled by an independent environmental assessment practitioner ( EAP ).8. Unless protected by law, all information in the report will become public information on receipt by the

competent authority. Any interested and affected party should be provided with the information contained in this report on request, during any stage of the application process.


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9. The KZN Department of Agriculture & Environmental Affairs may require that for specified types of activities in defined situations only parts of this report need to be completed.

10. The EAP must submit this basic assessment report for comment to all relevant State departments that administer a law relating to a matter affecting the environment. This provision is in accordance with Section 24 O (2) of the National Environmental Management Act 1998 (Act 107 of 1998) and such comments must be submitted within 40 days of such a request.

11. Please note that this report must be handed in or posted to the District Office of the KZN Department of Agriculture & Environmental Affairs to which the application has been allocated (please refer to the details provided in the letter of acknowledgement for this application).


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DEPARTMENTAL REFERENCE NUMBER(S)File reference number (EIA):

File reference number (WasteManagement Licence):

SECTION A: DETAILS OF THE ENVIRONMENTAL ASSESSMENT PRACTITIONER AND SPECIALISTS1. NAME AND CONTACT DETAILS OF ENVIRONMENTAL ASSESSMENT PRACTITIONER (EAP)

Name and contact details of the EAP who prepared this report:

Business name of EAP:

FutureWorks

Physical address:

Gardenia House, Fairway Green Office Park, 3 Abrey Rd, Kloof, Durban

Postal address: P.O. Box 2221, EvertonPostal code: 3625 Cell: 082 492 6804Telephone: 031-764 6449 Fax: 031-764 4907E-mail: [email protected]

2. NAMES AND EXPERTISE OF REPRESENTATIVES OF THE EAP

Names and details of the expertise of each representative of the EAP involved in the preparation of this report:

Name of representative of the EAP

Education qualifications

Professional affiliations

Experience at environmental assessments (yrs)

Ms Nicci DiederichsMander

BSc (Hons) Environmental Science

Certified Environmental Assessment Practitioner (EAPASA); Professional Natural Scientist (SACNASP)

16

Mr Michael Van Niekerk MSc Environmental Management

Certified Environmental Assessment Practitioner (EAPASA)

5.5


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3. NAMES AND EXPERTISE OF SPECIALISTS

Names and details of the expertise of each specialist that has contributed to this report:

Name of specialist

Education qualifications

Field of expertise

Section/ s contributed to in

this basic assessment

report

Title of specialist

report/ s as attached in Appendix D

Dave Nozaic Civil engineer Sewagetreatment specialist

Project description

SewageTreatment Design Report

Alan Spence Civil engineer Quantity surveyor Project description

Site Development Plan

Chris Krause BSc SurveyDiploma Datametrics

Land surveyorTownship planning

Project description

N/A


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SECTION B: ACTIVITY INFORMATION

1. PROJECT TITLE

Describe the project title as provided on the application form for environmental authorization:

Construction of a package sewage treatment plant, sewerage and stormwater infrastructure within a sensitive natural environment at Crowhurst Estate.

2. PROJECT DESCRIPTION

Provide a detailed description of the project:

Crowhurst Estate is a residential development located in Everton (Durban), comprising 12 five-bedroom units and associated infrastructure (i.e. roads, water, stormwater etc.) aimed at servicing the high-income housing market.

The total area of the development site is 2.6 ha, and includes a non-perennial drainage line in the western corner.

The site development plan for Crowhurst Estate was first approved by the eThekwini Municipality on 26 February 2007 (see Appendix G), and construction started on that basis. Due to a subsequent slump in the property market, construction was never completed. In 2012, minor amendments were made to the site development plan, which were approved by the eThekwini Municipality on 5 March 2013 (see Appendix G). No Application for Environmental Authorisation was conducted preceding or during the original application for development approval in 2006/7, as the national EIA Regulations in force at the time did not apply to any of the development activities proposed.

The intention is now to pursue completion of the development, with proposed further changes to the site development plan (which are not yet approved by the eThekwini Municipality). The major change involves the construction of a package sewage treatment plant to service the development, instead of the previously approved septic tanks and soakaway systems. This proposal has been made to address problems in the plan with fitting the septic tanks, soakaways and sufficient suitable evapotranspiration area onto the earth platforms which are to be created for the units. There was a concern that the on-site sewage system was difficult to accommodate properly on each of the erven, and would severely limit the potential size of the units given that parts of the site are steep and on-site sewage disposal posed an environmental risk.

While the proposed package sewage treatment plant does not require Environmental Authorisation in respect of its wastewater throughput (the treatment plant is expected to treat 30 m3 per day of sewage, which is thus well below the 2,000 m3 per day threshold specified in GNR544 of 2010 as requiring environmental authorisation), Environmental Authorisation is however required for the construction andoperation of the proposed package sewage treatment plant and portions of the proposed sewerage and stormwater reticulation system, which fall within 32 metres of the edge of the drainage line on the property. The Basic Assessment therefore focuses on how the activity of constructing and operating this infrastructure may impact on sensitive natural environments on the property.

The revised site development plan (Dwg. no. 1023-801 REV B), which incorporates these changes, will only be finalised and submitted to the eThekwini Municipality for approval following the outcome of this Application for Environmental Authorisation.


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It is proposed that the package sewage treatment plant will be located on the existing earth platform in the western corner of the site, adjacent the non-perennial drainage line. As such, the proposed package sewage treatment plant and associated sewerage pipelines are located within 32 metres of the said drainage line see Figure 1 below.

The site proposed for construction of the package sewage treatment plant was selected as it is the lowest point on the property, thus allowing wastewater to be gravity fed from the 12 units (note that each unit will have a septic tank, which discharges into the sewerage) down to this point for treatment. This location is optimal from an engineering design point of view, as it negates the need for pumpstations to be constructed to pump the raw sewage to the point of treatment. Pumpstations are energy intensive and are often points of sewage spillage as a result of pump failure and other problems in the pumping system.

No other site options for the package sewage treatment plant are considered in this report, as there are no other vacant areas on the property that are below the majority of the residential erven, large enough to accommodate the treatment plant, and potentially accessible by vehicle (note that the north-westernpart of the property is oversteep).

Access to the treatment plant site will be either from the exiting road which crosses the drainage line below the stormwater attenuation dam or from a small access road which runs alongside the south-western boundary of the property. As these roads cannot accommodate large vehicles, the haulage trucks deliverying the components of the treatment plant may need to park on the relatively wide verge on Ashley Drive and lift the components over the boundary wall and into position on the platform. Similarly, honeysuckers may also need to park on the verge of Ashley Drive and pump sewage sludge from the treatment plant over the boundary wall to the truck.


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Figure 1: Proposed site development plan showing the position of proposed package sewage treatment plant in relation to the drainage line

There are currently two infrastructure layout options are assessed in this BAR for the pipelines carrying treated sewage effluent leaving the package sewage treatment plant and transferring it to stream for discharge. These two layout alternatives are detailed below.

The first option, which is the preferred layout alternative A1, is for the treated sewage effluent to drain into the existing stormwater attenuation dam on site for final polishing see Figure 2 below. From the stormwater attenuation dam, the treated sewage effluent, which is further diluted with stormwater, will feed into an underground stormwater pipeline that is to run down to the Mphiti River, approximately 150m away in a north-westerly direction. This pipeline will need to cross the private property (3 Noelle Drive) directly adjacent to and downstream of Crowhurst Estate. Note that the proposed underground pipeline will replace an existing stormwater pipeline that runs along the surface across this neighbouring property. A drainage servitude already exists across this property and it is proposed that the upgraded stormwater / treated sewage effluent discharge pipeline is kept within this servitude, replacing the existing surface pipeline in this location.

See Fig. 2 below for enlargement of this area

Proposed location of package sewage treatment plant

Existing stormwater attenuation dam

Stormwater pipeline down to the Mphiti River

Drainage line

Ashely Drive verge to be used by large

trucks

Alternate access alongside south-

western boundary

Existing road access below dam


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Figure 2: Proposed site development plan showing position of proposed package sewage treatment plant, stormwater attenuation dam, and stormwater pipeline down to the Mphiti River

It is proposed that treated sewage will discharge into the upper tier of the attenuation dam to prolong the time that the treated sewage is retained, thereby maximising the uptake or assimilation of excess nutrients (i.e. polishing of the final treated effluent). The dam will also be planted with range of wetland plants, such as reeds, sedges, and papyrus, for aesthetic purposes, as well as to assimilate any excess nutrients. The other advantage of this option is the stormwater attenuation dam provides an importantbuffer in the event that the treatment plant fails, as the treated sewage effluent is not discharged directly into the Mphiti River. Thus, in the event that the treatment plant fails, sub-standard treated effluent can be temporarily stored in the attenuation dam until the treatment plant is operating properly (note that the dam can be pumped using a honeysucker and the sewage removed to a municipal sewage works for disposal in this instance, or stored in the dam and then pumped back into the treatment plant for re-treatment prior to discharge to the Mphiti River).

Proposed location of package sewage treatment plant

Stormwater pipeline down to Mphiti River

Dam wall

Dividing wall between upper and lower tier


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Figure 3: Existing dam to be used for stormwater attenuation and final polishing of treated sewage

The maximum capacity of the existing dam is 260 m3. This provides sufficient storage capacity for a 50 year storm event. It is proposed that the discharge from the stormwater attenuation dam is diverted into an underground pipeline that is to run down to the Mphiti River see Figure 4. The pipeline will be approximately 150 m in length and have an internal diameter of 0.315 m. The peak throughput capacity of the pipeline is 140 per second, which is able to accommodate the current stormwater peak flow of 137 per second and the 1.5 per second peak throughput of treated sewage.

Note that in terms of the design of the attenuation dam, the outflow pipeline will be located some 1.2m below the top of the dam wall, permitting constant outflow from the dam into the stormwater / sewage effluent pipeline, but ensuring that freeboard is maintained in the dam for stormwater attenuation. During a flood event of 1:50 years or more, the dam would be expected to overtop, and the water flowing over the wall would be flow into the drainage line as surface flow.

Upper tier

Dam wallLower tier

Dividing wall between upper and lower tier

Outflow from treatment plant


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Figure 4: Proposed alignment of pipeline down to Mphiti River

The outfall of the pipeline will be located immediately upstream of the existing culvert which runs underneath Noelle Drive. It is proposed that the outflow of the pipeline will be directed by a concrete dish into the culvert to ensure that stormwater outflows do not undercut the culvert or compromise the integrity of the Noelle Drive see Figure 4. The headwalls on either side of the culvert below Noelle Drive will also be upgraded as they currently in a state of disrepair. As the internal diameter of the existing culvert (0.45 m) is greater than that of the proposed pipeline (0.315 m), the Applicant s Engineer considers that there is sufficient capacity to accommodate the peak stormwater throughput(1:50 year event) from Crowhurst Estate. Infrequent flood events of much greater magnitude would be expected to result in localised, temporary pooling of stormwater around the culvert where the pipe size is insufficient to drain stormwater inflows from Crowhurst and the surrounding landscape.

Outfall of stormwater pipeline

Existing culvert below Noelle Drive

Proposed alignment of stormwater pipeline

Registered drainage servitude

Existing house at 3 Noelle Drive built over

drainage line

Proposed location of treatment plant


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Figure 5: Existing stormwater culvert below Noelle Drive

On the opposite end of the culvert, there is a grassed open channel (V-drain) down to the Mphiti River.This V-drain is relatively incised due to the current stormwater outflows from Crowhurst Estate, and would need to be stabilised to prevent future erosion. Stabilisation in this area would include LOW KEY interventions such as introducing rock pack. No major construction works is planned for this area.

Figure 6: Grassed open channel down to Mphiti River

The second layout option (A2) involves the treated sewage effluent being pumped approximately 180macross the length of the site to the northern corner. As shown in Figure 7, the sewerage pipeline, which would run underground, will closely follow the north-western boundary, needing to cross the drainage line just below the proposed package sewage treatment plant.

Figure 7: Proposed alternative sewerage pipeline from package sewage treatment plant to the Mphiti River

Proposed location of treatment plant

Opposite end of culvert below Noelle Drive

Mphiti River

Culvert below Noelle Drive

Proposed outfall of pipeline

Proposed concrete dish to direct flows

into culvert

Grassed open channel to Mphiti

River

Proposed location of pumpstation

Proposed sewerage pipeline

Drainage line crossing

Culvert headwall which will be repaired


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From the northern corner of the site, the treated sewage effluent will feed via gravity in an underground pipeline along the boundary of the adjacent private property (76 Everton Road). This property is approximately 3 hectares in extent and contains three residential units, as well as several large off-stream dams. The proposed sewerage pipeline will be located within the existing stormwater servitude registered along the property s southern boundary see Figure 8. A headwall will need to be constructed at the outfall into the Mphiti River.

Figure 8: Proposed sewerage pipeline through 76 Everton Rd

This sewerage pipeline would be considerably smaller than the stormwater and sewerage pipeline for the preferred layout alternative as it only has to accommodate 1.5 per second peak throughput of treated sewage effluent and would not include stormwater. This option also does not utilise the stormwater attenuation dam on the property for final polishing of the effluent and would not have this feature available to temporarily store treated effluent for removal / re-treatment in the case of package sewage treatment plant failure or overflow.

In this alternative, the stormwater discharge from Crowhurst Estate s attenuation dam would still be routed through the 3 Noelle Drive property either in the existing surface pipeline or in a new underground pipeline.

Stormwater servitude along southern boundary

of 76 Everton Rd Mphiti River

Off-stream dams

Crowhurst manor

Property boundary

Outfall into Mphiti River

Proposed sewerage pipeline


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3. ACTIVITY DESCRIPTION

Describe each listed activity in Listing Notice 1 (GNR 544, 18 June2010), Listing Notice 3 (GNR 546, 18 June 2010) or Category A of GN 718, 3 July 2009 (Waste Management Activities) which is being applied for as per the project description:

GNR 544 (11): The construction of

(vi) bulk storm water outlet structures;(x) buildings exceeding 50 square metres in size; or(xi) infrastructure or structures covering 50 square metres or more

where such construction occurs within a watercourse or within 32 metres of a watercourse...

The proposed package sewage treatment plant, sewerage and stormwater pipelines described in Section 2 of this report comprise the listed development activities above insofar as where these buildings and infrastructure falls within 32m of the drainage line on the property and the Mphiti River.

GNR 544 (18): The infilling or depositing of any material of more than 5 cubic metres into, or the dredging, excavation,

removal or moving of soil, sand, shells, shell grit, pebbles or rock or more than 5 cubic metres from(i) a watercourse

The proposed construction of an underground pipeline to carry stormwater and treated sewage effluent from the stormwater attenuation dam to the discharge point at the road culvert in Noelle Road (and repairs / stabilisation of the V-drain below Noelle Dv) would require more than 5m3 of soil in the drainage line to be moved.

4. FEASIBLE AND REASONABLE ALTERNATIVES

alternatives , in relation to a proposed activity, means different means of meeting the general purpose and requirements of the activity, which may include alternatives to(a) the property on which or location where it is proposed to undertake the activity;(b) the type of activity to be undertaken;(c) the design or layout of the activity;(d) the technology to be used in the activity;(e) the operational aspects of the activity; and(f) the option of not implementing the activity.

Describe alternatives that are considered in this report. Alternatives should include a consideration of all possible means by which the purpose and need of the proposed activitycould be accomplished in the specific instance taking account of the interest of the applicant in the activity. The no-go alternative must in all cases be included in the assessment phase as the baseline against which the impacts of the other alternatives are assessed. The determination of whether site or activity (including different processes etc.) or both is appropriate needs to be informed by the specific circumstances of the activity and its environment. After receipt of this report the competent authority may also request the applicant to assess additional alternatives that could possibly accomplish the purpose and need of the proposed activity if it is clear that realistic alternatives have not been considered to a reasonable extent.


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Sections B 5 15 below should be completed for each alternative.

5. ACTIVITY POSITION

Indicate the position of the activity using the latitude and longitude of the centre point of the site for each alternative site. The co-ordinates should be in degrees, minutes and seconds. List alternative sites were applicable.

Alternative:Latitude (S): Longitude (E):

Alternative S11 (preferred or only site alternative) Note that this is the position of the proposed packagesewage treatment plant

29o 47 5.284 30o 48 40.007

Alternative S2 (if any) o o

Alternative S3 (if any) o o

In the case of linear activities:Alternative: Latitude (S): Longitude (E):Alternative S1 (preferred or only route alternative)• Starting point of the activity o o

• Middle point of the activity o o

• End point of the activity o o

Alternative S2 (if any)• Starting point of the activity o o



Alternative S3 (if any)• Starting point of the activity o o



For route alternatives that are longer than 500m, please provide an addendum with co-ordinates taken every 500m along the route for each alternative alignment.

6. PHYSICAL SIZE OF THE ACTIVITY

Indicate the physical size of the preferred activity/technology as well as alternative activities/technologies (footprints):Alternative: Size of the activity:Alternative A12 (Size of package sewage treatment plant)

235 m2

Alternative A2 (if any) m2


1 Alternative S.. refer to site alternatives.2 Alternative A.. refer to activity, process, technology or other alternatives.


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or, for linear activities:

Alternative: Length of the activity:

Alternative A1 (Pipelines routing through the attenuation dam, and down through the adjacent property to discharge upstream of culvert under Noelle Drive)

250 m

Alternative A2 (Sewage effluent pipeline route from the package sewage treatment plant, across the drainage line, along the north-western boundary of the property, down the southern boundary of the adjacent property below Crowhurst Manor, and down to the Mphiti River not including the stormwater pipeline from the attenuation dam to the Mphiti)

285 m

Alternative A3 (if any) m

Indicate the size of the alternative sites or servitudes (within which the above footprints will occur):Alternative: Size of the

site/servitude:Alternative A1 (Crowhurst Estate) 25,894 m2



7. SITE ACCESS

Does ready access to the site exist? YESIf NO, what is the distance over which a new access road will be built mDescribe the type of access road planned:

Include the position of the access road on the site plan and required map, as well as an indication of the road in relation to the site.

8. SITE OR ROUTE PLAN

A detailed site or route plan(s) must be prepared for each alternative site or alternative activity. It must be attached as Appendix A to this report.

The site or route plans must indicate the following:8.1. the scale of the plan which must be at least a scale of 1:500;8.2. the property boundaries and numbers/ erf/ farm numbers of all adjoining properties of

the site; 8.3. the current land use as well as the land use zoning of each of the properties adjoining

the site or sites;


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8.4. the exact position of each element of the application as well as any other structures on the site;

8.5. the position of services, including electricity supply cables (indicate above or underground), water supply pipelines, boreholes, street lights, sewage pipelines, storm water infrastructure and telecommunication infrastructure;

8.6. walls and fencing including details of the height and construction material; 8.7. servitudes indicating the purpose of the servitude; 8.8. sensitive environmental elements within 100 metres of the site or sites including (but

not limited thereto):� rivers, streams, drainage lines or wetlands;� the 1:100 year flood line (where available or where it is required by DWA);� ridges;� cultural and historical features;� areas with indigenous vegetation including protected plant species (even if it is

degraded or infested with alien species);8.9. for gentle slopes the 1 metre contour intervals must be indicated on the plan and

whenever the slope of the site exceeds 1:10, the 500mm contours must be indicated on the plan; and

8.10. the positions from where photographs of the site were taken.

9. SITE PHOTOGRAPHS

Colour photographs from the centre of the site must be taken in at least the eight major compass directions with a description of each photograph. Photographs must be attached under Appendix B to this report. It must be supplemented with additional photographs of relevant features on the site, if applicable.

10. FACILITY ILLUSTRATION

A detailed illustration of the facility must be provided at a scale of 1:200 and attached to this report as Appendix C. The illustrations must be to scale and must represent a realistic image of the planned activity/ies.

11. ACTIVITY MOTIVATION

11.1. Socio-economic value of the activityWhat is the expected capital value of the activity on completion? R72 millionWhat is the expected yearly income that will be generated by or as a result of the activity? Estimated annual rates income to the metro municipality.

R 360,000

Will the activity contribute to service infrastructure? NOIs the activity a public amenity? NOHow many new employment opportunities will be created in the development phase of the activity?

142

What is the expected value of the employment opportunities during the development phase?

R10 million

What percentage of this will accrue to previously disadvantaged individuals? 70%How many permanent new employment opportunities will be created during the operational phase of the activity?

13


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What is the expected current value of the employment opportunities during the first 10 years?

R4 million

What percentage of this will accrue to previously disadvantaged individuals? 100%

11.2. Need and desirability of the activity

Motivate and explain the need and desirability of the activity (including demand for the activity):

The proposed package sewage treatment plant, sewerage and stormwater infrastructure within a sensitive environment (i.e. drainage line) at Crowhurst Estate is required to service Crowhurst Estate, a residential development, comprising 12 five-bedroom units, already approved by the eThekwini Municipality.

The development of Crowhurst Estate is driven by a demand for medium density housing, aimed at servicing the high-income market, within the suburb of Everton, as well a need to maximize the use of remaining land opportunities.

Crowhurst Estate was previously approved as a development that would be serviced by on-site sanitation systems comprising septic tanks and soakaways. However, this form of sanitation servicing requires large tracts of relatively flat, vegetated land to properly allow evapotranspiration. At Crowhurst, this was not a simple matter, as parts of the site are steep and the proposed sanitation system would pose a risk in certain locations in terms of environmental contamination (where soakaways are located close to fill embankments) and would severely limit the sizes of the units (i.e. the larger the unit, the larger the evapotranspiration area needed to provide for proper wastewater disposal). As such, the Applicant deemed that a package sewage treatment plant would be a preferable option, as this would permit larger units (which is the market segment being targeted with the Crowhurst Estate development) and less risk of failure and contamination from on-site sanitation systems operating in sub-optimal topographic conditions.

The proposed development of Crowhurst Estate, serviced by a package sewage treatment plant, which would allow maximisation of the size and value of the units within the estate, is considered to present the means to achieving the highest and best use of the land.

In terms of the above context, the package sewage treatment plant proposed to be constructed to service the Crowhurst Estate falls below the thresholds of the National Environmental Impact Assessment Regulations, in terms of an amendment to these regulations published on 29 November 2013 (GNR922/2013). As such, the potential effects of the treatment plant on the receiving water resources environment will be assessed by the Department of Water Affairs (DWA) when the Applicant submits its application to register the package sewage treatment plant as a water user and / or apply for any applicable permits from DWA.

The proposed package sewage treatment plant, and associated downstream pipelines (as well as stormwater pipelines that are to be upgraded to accommodate the development of Crowhurst Estate) do, however, require Environmental Authorisation in respect of their construction and operation in close proximity to and / or within the drainage line. It is therefore the impact of the construction and operationof these facilities on the drainage line that is the focus of this report.

Given the layout of the development and the lie of the land, it is likely that without the proposed package sewage treatment plant and sewerage infrastructure being located within or in close proximity to the drainage line, it would be necessary to pump sewage across the site. The proposed location of the package sewage treatment plant allows raw sewage to feed via gravity to the proposed treatment plant, and treated sewage effluent from the treatment plant down to the stormwater attenuation dam for final polishing, and stormwater and treated sewage effluent from the stormwater attenuation dam down


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to the Mphiti River. There are no other low points on the property that are accessible or large enough to accommodate the package sewage treatment plant and thus avoid the need to pump sewage. The pumping of sewage is considered undesirable owing to the need to run energy intensive pumps and the fact that these installations are prone to overflows and spillage during electricity outages and as a result of pump failure.

It is therefore considered desirable from a site development point of view to pursue development of the package sewage treatment plant, and associated pipelines, within or in close proximity to the drainage line. This is deemed to offer the best fit option from an engineering and environmental risk management perspective.

Indicate any benefits that the activity will have for society in general:

The proposed development contributes to the supply of high-end medium density housing which is currently a high demand in the suburb of Everton.

In approving Crowhurst Estate, the eThekwini Municipality is responding to a need to utilise the capacity of the outer west region of the Municipal Area to accommodate growth through the densification of some areas and / or opening up of vacant or underutilized land.

Indicate any benefits that the activity will have for the local communities where the activity will be located:

The construction of the package sewage treatment plant and sewerage pipelines, and expansion/upgrading of existing stormwater infrastructure will generate temporary employment during the construction phase and permanent employment opportunities during the operational phase.

Further to this, the existing stormwater pipeline through the property below Crowhurst Estate, which is unsightly and leaking, will be replaced by a new pipeline which will run underground down to the Mphiti River.

12. APPLICABLE LEGISLATION, POLICIES AND/OR GUIDELINES

List all legislation, policies and/or guidelines of any sphere of government that are relevant to the application as contemplated in the EIA regulations, if applicable:

Title of legislation, policy or guideline: Administering authority: Date:

The Constitution (108 of 1996)

National Environmental Management Act (107 of 1998)

National Water Act (36 of 1998)

National Environmental Management: Waste Act (59 of 2008)

GNR 543 (2010)

GNR 544 (2010)

DEA

DWA

DEA

DEA

DEA

1996

1998

1998

2008

2010

2010


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GNR 546 (2010)

GNR 922 (2013)

Guideline for the Design and Approval of on Site (Sub-surface) Disposal of Domestic Sewage.

DEA

DEA

eThekwini Municipality

2010

2013

2001

13. WASTE, EFFLUENT, EMISSION AND NOISE MANAGEMENT

13.1. Solid waste management

Will the activity produce solid construction waste during the construction/initiation phase?

NO

If yes, what estimated quantity will be produced per month? m3

How will the construction solid waste be disposed of? (describe)

Where will the construction solid waste be disposed of? (provide details of landfill site)

Will the activity produce solid waste during its operational phase? YESIf yes, what estimated quantity will be produced per month? < 100m3

How will the solid waste be disposed of? (provide details of landfill site)

The package sewage treatment plant will produce sludge which will be removed by a licensed contractor and disposed of at a municipal treatment works. The volumes are considered to be very low and the frequency of desludging very infrequent.

Crowhurst Estate will produce normal quantities and types of domestic solid waste.

Where will the solid waste be disposed if it does not feed into a municipal waste stream (describe)?N/AIf the solid waste (construction or operational phases) will not be disposed of in a registered landfill site or be taken up in a municipal waste stream, then the applicant should consult with the competent authority to determine the further requirements of the application.Can any part of the solid waste be classified as hazardous in terms of the relevant legislation?

NO

If yes, contact the KZN Department of Agriculture & Environmental Affairs to obtain clarity regarding the process requirements for your application. Is the activity that is being applied for a solid waste handling or treatment facility?

NO

If yes, contact the KZN Department of Agriculture & Environmental Affairs to obtain clarity regarding the process requirements for your application.

13.2. Liquid effluent

Will the activity produce effluent, other than normal sewage, that will be disposed of in a municipal sewage system?

NO


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If yes, what estimated quantity will be produced per month? m3

Will the activity produce any effluent that will be treated and/or disposed of on site?

YES

If yes, contact the KZN Department of Agriculture & Environmental Affairs to obtain clarity regarding the process requirements for your application. This has been done and it was deemed that the current Application for Environmental Authorisation, subject to Basic Assessment, was the correct process to follow.Will the activity produce effluent that will be treated and/or disposed of at another facility?

NO

If yes, provide the particulars of the facility:Facility name:Contact person:Postal address:Postal code:Telephone: Cell:E-mail: Fax:Describe the measures that will be taken to ensure the optimal reuse or recycling of waste water, if any:

13.3. Emissions into the atmosphere

Will the activity release emissions into the atmosphere? NOIf yes, is it controlled by any legislation of any sphere of government? YES NOIf yes, contact the KZN Department of Agriculture & Environmental Affairs to obtain clarity regarding the process requirements for your application.If no, describe the emissions in terms of type and concentration:

13.4. Generation of noise

Will the activity generate noise? NOIf yes, is it controlled by any legislation of any sphere of government? YES NOIf yes, the applicant should consult with the competent authority to determine whether it is necessary to change to an application for scoping and EIA. If no, describe the noise in terms of type and level:

14. WATER USE

Please indicate the source(s) of water that will be used for the activity by ticking the appropriate box(es):

municipal

If water is to be extracted from groundwater, river, stream, dam, lake or any litres


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other natural feature, please indicate the volume that will be extracted per month:Does the activity require a water use permit from the Department of Water Affairs?

NO

If YES, please submit the necessary application to the Department of Water Affairs and attach proof thereof to this report.

15. ENERGY EFFICIENCY

Describe the design measures, if any, that have been taken to ensure that the activity is energy efficient:

It is proposed that all units at the Crowhurst Estate be fitted with low-flow showerheads and dual-flush toilets to reduce the amount of sewage requiring to be treated by the package sewage treatment plant, thereby reducing the amount of energy required to operate the treatment plant.

Describe how alternative energy sources have been taken into account or been built into the design of the activity, if any:

SECTION C: SITE/ AREA/ PROPERTY DESCRIPTION

Important notes:• For linear activities (pipelines, etc.) as well as activities that cover very large sites, it may

be necessary to complete this section for each part of the site that has a significantly different environment. In such cases please complete copies of Section C and indicate the area, which is covered by each copy No. on the Site Plan.

Section C Copy No. (e.g. A):

• Subsections 1 - 6 below must be completed for each alternative.

1. GRADIENT OF THE SITE

Indicate the general gradient of the site.Alternative S1:

Flat 1:7,5 1:5Alternative S2 (if any):

Flat 1:50 1:20 1:20 1:15 1:15 1:10 1:10 1:7,5 1:7,5 1:5 Steeper than1:5

Alternative S3 (if any):Flat 1:50 1:20 1:20 1:15 1:15 1:10 1:10 1:7,5 1:7,5 1:5 Steeper than

1:5


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2. LOCATION IN LANDSCAPE

Indicate the landform(s) that best describes the site (Please cross the appropriate box).Alternative S1 (preferred site):

Side slope of hill/mountain

Openvalley

Alternative S2 (if any):Ridgeline Plateau Side slope of

hill/mountainClosed valley

Openvalley

Plain Undulating plain/low hills

Dune Sea-front

Alternative S3 (if any):Ridgeline Plateau Side slope of

hill/mountainClosed valley

Openvalley

Plain Undulating plain/low hills

Dune Sea-front

3. GROUNDWATER, SOIL AND GEOLOGICAL STABILITY OF THE SITE

Is the site(s) located on any of the following (cross the appropriate boxes)?Alternative S1: Alternative S2 (if

any):Alternative S3 (if any):

Shallow water table (less than 1.5m deep)

YES YES NO YES NO

Dolomite, sinkhole or doline areas NO YES NO YES NO

Seasonally wet soils (often close to water bodies)

YES YES NO YES NO

Unstable rocky slopes or steep slopes with loose soil

NO YES NO YES NO

Dispersive soils (soils that dissolve in water)

NO YES NO YES NO

Soils with high clay content (clay fraction more than 40%)

NO YES NO YES NO

Any other unstable soil or geological feature

NO YES NO YES NO

An area sensitive to erosion NO YES NO YES NO

If you are unsure about any of the above or if you are concerned that any of the above aspects may be an issue of concern in the application, an appropriate specialist should be appointed to assist in the completion of this section. (Information in respect of the above will often be available as part of the project information or at the planning sections of local authorities. Where it exists, the 1:50 000 scale Regional Geotechnical Maps prepared by the Council for Geo Science may also be consulted).

4. GROUNDCOVER

Has a specialist been consulted for the completion of this section? NOIf YES, please complete the following:Name of the specialist:Qualification(s) of the specialist:Postal address:Postal code:Telephone: Cell:E-mail: Fax:Are there any rare or endangered flora or fauna species (including red data species) present on any of the alternative sites?

NO


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If YES, specify and explain:Are there any special or sensitive habitats or other natural features present on any of the alternative sites?

YES

If YES, specify and explain:

Non-perennial stream in western part of site.

Are any further specialist studies recommended by the specialist? NOIf YES, specify:If YES, is such a report(s) attached in Appendix D? YES NO

Signature of specialist: Date:

The location of all identified rare or endangered species or other elements should be accurately indicated on the site plan(s).

Cross the types of groundcover present on the site.

Gardens Building or other structure

If any of the boxes marked with an E is ticked, please consult an appropriate specialist to assist in the completion of this section if the environmental assessment practitioner doesn t have the necessary expertise.

5. LAND USE CHARACTER OF SURROUNDING AREA

Cross the land uses and/or prominent features that currently occur within a 500m radius of the site and give a description of how this influences the application or may be impacted upon by the application:

Land use character DescriptionNatural area YES Everton Conservancy downstream of the

site, construction must avoid creating sediment in the stream that affects this area.Gillitts Conservancy (Mphiti Nature Reserve)

upstream of the property, no influence.Low density residential YES No influence. Medium density residential YES No influence. High density residential NOInformal residential NORetail commercial & warehousing NOLight industrial NOMedium industrial NOHeavy industrial NOPower station NOOffice/consulting room NOMilitary or police base/station/compound NOSpoil heap or slimes dam NOQuarry, sand or borrow pit NODam or reservoir NO


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Hospital/medical centre NOSchool/ crèche NOTertiary education facility NOChurch NOOld age home NOSewage treatment plant NOTrain station or shunting yard NORailway line NOMajor road (4 lanes or more) NOAirport NOHarbour NOSport facilities NOGolf course NOPolo fields NOFilling station NOLandfill or waste treatment site NOPlantation NOAgriculture NORiver, stream or wetland YES Mphiti River and fringing riparian vegetation

downstream of site sensitive receiving environment.

Nature conservation area YES Everton Conservancy downstream of the site, construction must avoid creating sediment in the stream that affects this area.Gillitts Conservancy (Mphiti Nature Reserve)

upstream of the property, no influence.Mountain, hill or ridge NOMuseum NOHistorical building NOProtected Area NOGraveyard NOArchaeological site NOOther land uses (describe) NO

6. CULTURAL/ HISTORICAL FEATURES

Are there any signs of culturally or historically significant elements, as defined in section 2 of the National Heritage Resources Act, 1999, (Act No. 25 of 1999), including archaeological or palaeontological sites, on or within 20m of the site?

NO

If YES, contact a specialist recommended by AMAFA to conduct a heritage impact assessment. The heritage impact assessment must be attached as an appendix to this report. Briefly explain the recommendations of the specialist:Will any building or structure older than 60 years be affected in any way? NOIs it necessary to apply for a permit in terms of the National Heritage Resources Act, 1999 (Act 25 of 1999)?

NO

If YES, please submit the necessary application to AMAFA and attach proof thereof to this report.


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SECTION D: PUBLIC PARTICIPATION

1. ADVERTISEMENT

The person conducting a public participation process must take into account any guidelines applicable to public participation as contemplated in section 24J of the Act and must give notice to all potential interested and affected parties of the application which is subjected to public participation by

(a) fixing a notice board (of a size at least 60cm by 42cm; and must display the required information in lettering and in a format as may be determined by the competent authority) at a place conspicuous to the public at the boundary or on the fence of(i) the site where the activity to which the application relates is or is to be

undertaken; and(ii) any alternative site mentioned in the application;

(b) giving written notice to(i) the owner or person in control of that land if the applicant is not the owner or

person in control of the land;(ii) the occupiers of the site where the activity is or is to be undertaken or to any

alternative site where the activity is to be undertaken;(iii) owners and occupiers of land adjacent to the site where the activity is or is to

be undertaken or to any alternative site where the activity is to be undertaken; (iv) the municipal councillor of the ward in which the site or alternative site is

situated and any organisation of ratepayers that represent the community in the area;

(v) the local and district municipality which has jurisdiction in the area; (vi) any organ of state having jurisdiction in respect of any aspect of the activity (as

identified in the application form for the environmental authorization of this project); and

(vii) any other party as required by the competent authority;(c) placing an advertisement in

(i) one local newspaper; or (ii) any official Gazette that is published specifically for the purpose of providing

public notice of applications or other submissions made in terms of these Regulations;

(d) placing an advertisement in at least one provincial newspaper or national newspaper, if the activity has or may have an impact that extends beyond the boundaries of the metropolitan or district municipality in which it is or will be undertaken: Provided that this paragraph need not be complied with if an advertisement has been placed in an official Gazette referred to in subregulation 54(c)(ii); and

(e) using reasonable alternative methods, as agreed to by the competent authority, in those instances where a person is desiring of but unable to participate in the process due to(i) illiteracy;(ii) disability; or(iii) any other disadvantage.


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2. CONTENT OF ADVERTISEMENTS AND NOTICES

A notice board, advertisement or notices must:(a) indicate the details of the application which is subjected to public participation; and (b) state

(i) that an application for environmental authorization has been submitted to theKZN Department of Agriculture & Environmental Affairs in terms of the EIA Regulations, 2010;(ii)

(iii) a brief project description that includes the nature and location of the activity to which the application relates;

(iv) where further information on the application can be obtained; and (iv) the manner in which and the person to whom representations in respect of the

application may be made.

3. PLACEMENT OF ADVERTISEMENTS AND NOTICES

Where the proposed activity may have impacts that extend beyond the municipal area where it is located, a notice must be placed in at least one provincial newspaper or national newspaper, indicating that an application will be submitted to the competent authority in terms of these regulations, the nature and location of the activity, where further information on the proposed activity can be obtained and the manner in which representations in respect of the application can be made, unless a notice has been placed in any Gazette that is published specifically for the purpose of providing notice to the public of applications made in terms of the EIA regulations.

Advertisements and notices must make provision for all alternatives.

4. DETERMINATION OF APPROPRIATE PROCESS

The EAP must ensure that the public participation process is according to that prescribed in regulation 54 of the EIA Regulations, 2010, but may deviate from the requirements of subregulation 54(2) in the manner agreed by the KZN Department of Agriculture &Environmental Affairs as appropriate for this application. Special attention should be given to the involvement of local community structures such as Ward Committees, ratepayers associations and traditional authorities where appropriate.

Please note that public concerns that emerge at a later stage that should have been addressed may cause the competent authority to withdraw any authorisation it may have issued if it becomes apparent that the public participation process was inadequate.

5. COMMENTS AND RESPONSE REPORT

The practitioner must record all comments and respond to each comment of the public before this application is submitted. The comments and responses must be captured in a comments and response report as prescribed in the EIA regulations (regulation 57 in the EIA Regulations, 2010) and be attached as Appendix E to this report.


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6. PARTICIPATION BY DISTRICT, LOCAL AND TRADITIONAL AUTHORITIES

District, local and traditional authorities (where applicable) are all key interested and affected parties in each application and no decision on any application will be made before the relevant local authority is provided with the opportunity to give input. The planning and the environmental sections of the local authority must be informed of this application and provided with an opportunity to comment.

Has any comment been received from the district municipality? NOIf YES , briefly describe the feedback below (also attach any correspondence to and from this authority with regard to this application):

Has any comment been received from the local municipality? YESIf YES , briefly describe the feedback below (also attach any correspondence to and from this authority with regard to this application):

See Appendix E: Issues and Responses Report.

Has any comment been received from a traditional authority? NOIf YES , briefly describe the feedback below (also attach any correspondence to and from this authority with regard to this application):

7. CONSULTATION WITH OTHER STAKEHOLDERS

Any stakeholder that has a direct interest in the site or property, such as servitude holders and service providers, should be informed of the application and be provided with the opportunity to comment.

Has any comment been received from stakeholders? YESIf YES , briefly describe the feedback below (also attach copies of any correspondence to and from the stakeholders to this application):

See Appendix E: Issues and Responses Report.


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SECTION E: IMPACT ASSESSMENT

The assessment of impacts must adhere to the requirements in the EIA Regulations, 2010, and should take applicable official guidelines into account. The issues raised by interested and affected parties should also be addressed in the assessment of impacts.

1. ISSUES RAISED BY INTERESTED AND AFFECTED PARTIES

List the main issues raised by interested and affected parties.

1. Site development plan and building plans have not been approved by eThekwini Municipality.

2. Impact of proposed activities on non-perennial stream through property.

3. Impact on Mphiti River of increased stormwater runoff and discharge of treated sewage effluent from Crowhurst Estate.

4. Stormwater runoff from increased hardened surfaces.

5. Structural stability of existing dam, and capacity to attenuate increased stormwater runoff.

6. Protection of on-site drainage line and green open spaces from future development.

7. Impact on value of adjacent properties.

8. Increased traffic on Everton Road.

Response from the practitioner to the issues raised by the interested and affected parties (A full response must be given in the Comments and Response Report that must be attached as Appendix E to this report):

1. Site development plan and building plans have not been approved by eThekwini Municipality.

The site development plan for Crowhurst Estate was first approved by the eThekwini Municipality on 26 February 2007, and construction started on that basis. Due to a subsequent slump in the property market, construction was never completed. In 2012, minor amendments were made to the 2007 site development plan, which were approved by the eThekwini Municipality on 5 March 2013. The intention is now to pursue completion of the development, with certain changes to the site development plan in place. The revised site development plan (Dwg. no. 1023-801 REV B), which incorporates these changes, will only be finalised and submitted to the eThekwini Municipality for approval following completion of this Application for Environmental Authorisation and Basic Assessment process.

2. Impact of proposed activities on non-perennial stream through property.

During the construction phase, the proposed activities may have a limited impact on the non-perennial stream area on the property with the replacement of the existing stormwater pipeline. During the operational phase, the drainage line may become drier as the majority of rainfall falling on the property will be directed into the stormwater attenuation dam. While this will be to the benefit of the landowner adjacent to and downstream of Crowhurst Estate, whose house is located within the erstwhile drainage line, the existing ecology within the drainage line will be negatively affected.


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The impact will however limited as the drainage line has been drained via a stormwater pipeline for decades. As such, the drainage line is highly transformed hydrologically and ecologically, and severely degraded due to alien plant infestations and dumping which has taken place there for many years. Inmitigation, the drainage line will be rehabilitated and planted with coastal riparian vegetation that is more tolerant of the drier conditions. Periodic wetting of the drainage line may still occur in major flood events when the stormwater attenuation dam overtops and the vegetative rehabilitation programme will need to be cognisant of this need for the water to flow on the surface without damaging the fence or downstream property.

3. Impact on Mphiti River of increased stormwater runoff and discharge of treated sewage from Crowhurst Estate.

The impact of the proposed activities on the Mphiti River is likely to be limited. Stormwater attenuation must be undertaken on the property as required by the eThekwini Municipality; this would limit the negative effects of increased peak discharge from accelerated stormwater flows. The additional flow from the package sewage treatment plant (1.5 litres per second) is low and unlikely to contribute negatively to peak flow in the Mphiti and may in fact contribute positively to marginally raising low flow / baseflow levels.

The limited quantities of treated sewage effluent being discharged into the Mphiti would be unlikely to have a negative effect on the ecology of the river, particularly if the treated sewage effluent were to be mixed with stormwater prior to being discharged as is proposed in the preferred development option.

4. Stormwater runoff from increased hardened surfaces.

The impact of stormwater runoff from the increased hardened surfaces is likely to be negligible, as almost all the stormwater runoff from hardened surfaces will be captured and directed into the stormwater attenuation dam. In terms of the eThekwini Municipality s stormwater management requirements, peak stormwater flow post-development may not exceed peak stormwater flow pre-development, and this has been addressed in the stormwater management plan for the development.

5. Structural stability of existing dam, and capacity to attenuate increased stormwater runoff.

The existing stormwater attenuation dam was designed by a suitably qualified engineer and is therefore considered to be structurally sound. The total storage volume is 260 m3, which is sufficient to attenuate stormwater runoff for a 50-year storm.

6. Protection of on-site drainage line and green open spaces from future development.

It is proposed that the on-site drainage line and the adjacent embankments be registered as a Non-User Conservation Servitude (NUCS) or Conservation Zone, to protect these areas from development in the future.

7. Impact on value of adjacent properties.

This impact is likely to be negligible as the proposed development is aimed at servicing the high-income housing market, and as such is likely to have a high level of management.

8. Increased traffic on Everton Road.

This impact is likely to be negligible as the proposed development only comprises 12 units.


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2. IMPACTS THAT MAY RESULT FROM THE PLANNING AND DESIGN, CONSTRUCTION, OPERATIONAL, DECOMMISSIONING AND CLOSURE PHASES AS WELL AS PROPOSED MANAGEMENT OF IDENTIFIED IMPACTS AND PROPOSED MITIGATION MEASURES

2.1. IMPACTS THAT MAY RESULT FROM THE PLANNING AND DESIGN PHASE

a. Site alternatives

List the potential impacts associated with site alternatives that are likely to occur during the planning and design phase:

Alternative S1 (preferred alternative)

Site Alternative 1 is the proposed location of the package sewage treatment plant on an existing platform, within 32m of the drainage line, in the western corner of the Crowhurst Estate development property.

Direct impacts:

Positioning of the package sewage treatment plant, and associated infrastructure in close proximity to the drainage line resulting in construction needing to happen in a sensitive environment.

• The impact is negative and of low significance. • The package sewage treatment plant and associated infrastructure are located well outside the drainage

line (>15m), which is steeply incised at this point so the distance is also associated with a significant elevation of this infrastructure above the base of the drainage line.

• Further to this, the drainage line has a low functionality, having previously been disturbed by earthworks, construction of a pipeline in it, and dumping of various rubbish in the drainage line. In addition, the ecological linkage with the Mphiti River and regional river network has been historically broken by piping of the water flow from the stormwater attenuation dam through the property immediately downstream of the development. Note that a house is also built over the erstwhile drainage line on this adjacent property.

Positioning of the package sewage treatment plant in the proposed position where all sewage generated on the site can be gravity fed to this point, thereby eliminating the need for pumping of treated sewage effluent across the site.

• The impact is positive and the significance is moderate.• The siting of the package sewage treatment plant in such a way as to avoid the need for a pumpstation is

positive in that the negative energy usage impacts and environmental contamination risks associated with sewage pumping are avoided.

Indirect impacts:

None

Cumulative impacts:

Contribution to a proliferation of package sewage treatment plants in the outer west area of eThekwini Municipality, resulting in heightened risk to water resources.

• Negative impact, low significance.• While the principal of not supporting the proliferation of small package sewage treatment plants is

unquestionable, in this instance the treatment plant is small enough to present limited risk to local water resources, and probably is a less risk solution than on-site sanitation given the steepness of parts of the development site. Given that the development is already approved with on-site sanitation, this is in fact the default position and could be pursued if the proposed package sewage treatment plant does not receive the required approvals.

• Each unit at Crowhurst will have a septic tank that will treat domestic wastewater to a primary level. The package plant will treat this septic tank water. As such two levels of domestic wastewater treatment would be taking place at Crowhurst, thereby limiting the risks to water resources to a significantly greater extent than the on-site sanitation option presents.

Alternative S2 (if any)Direct impacts:

Indirect impacts:

Cumulative impacts:


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No-go alternative (compulsory)

The no-go alternative would involve not planning for the construction of the package sewage treatment plant, and not constructing such. The implication would be that the development was constructed as already approved and was serviced with on-site sanitation involving septic tanks and soakaways.

Direct impacts:

No loss of open space in the western corner of the site this remains undeveloped.• Positive impact, low significance owing to the limited ecological and or recreational value of this area, being

mostly steep and heavily overgrown with garden plants at the time of assessment.• The site of the proposed package sewage treatment plant is not in the drainage line and has limited

connectivity with other open spaces / hydrological systems in the area.

Potential to achieve the highest and best land use potential may be limited by the fact that unit sizes are curtailed by the on-site sanitation capability of each erf within the estate.

• Negative impact, low significance.• The restriction may affect the marketability of the development and the returns to the developer. However,

in terms of meeting the need for medium density, high income housing in Everton this would be unlikely to be a fatal factor for the development.

Potential risk to natural environment may be increased by the on-site sanitation systems.• Negative impact, moderate significance.• On-site sanitation may work well for some of the erven within the development, but for the erven on the

north-western portion of the property, there isn t sufficient space to achieve optimum evapotranspiration on each erf, given the steepness of these sites on this portion of the property. As these sites have steep embankments. It is possible that poorly assimilated soakaway water would seep from the embankments and cause surface and ground water pollution.

Indirect impacts:

None.

Cumulative impacts:

None.

Indicate mitigation measures to manage the potential impacts listed above:

Alternative S1 Alternative S2None recommended.

b. Process, technology, layout or other alternatives

List the impacts associated with any process, technology, layout or other alternatives that are likely to occur during the planning and design phase (please list impacts associated with each alternative separately):

Alternative A1 (preferred alternative)

Alternative A1 involves the construction of a treated sewage effluent pipeline from the package sewage treatment plant to the existing stormwater attenuation dam, and a stormwater pipeline (underground) from this stormwater attenuation dam down the drainage line, into the downstream neighbouring property, and discharging upstream of the culvert under Noelle Rd some 150 m downstream of the stormwater dam.

Direct impacts:

Proposed construction of a stormwater (and treated sewage effluent transfer) pipeline (rather than an open channel for example) within the drainage line from the stormwater attenuation dam to the Noelle Dv culvert, resulting in transformation of the watercourse and clearing of natural vegetation.

• The impact is negative and the significance is low.• The drainage line has been drained via a stormwater pipeline for decades. As such, the drainage line is

highly transformed hydrologically and ecologically, and severely degraded due to alien plant infestationsand dumping which has taken place there for many years.

Proposed construction of a stormwater (and treated sewage effluent transfer) pipeline through the private property adjacent to and downstream of the development property, resulting in disturbance to the neighbour s property.

• The impact is both positive and negative, and the significance is low.• The positive element of this impact is related to the fact that previously, the affected neighbour has

suffered stormwater damage to his property as a result of the fact that the house is built over the drainage line. The upgrading of the stormwater pipeline through this property will reduce the risk of such stormwater damage occurring in future.


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• The negative element of this impact is related to the fact that, in order to service the Crowhurst Estate development from a stormwater discharge point of view, and a treated sewage effluent point of view, a pipeline must be built across a private property. Note that there is an existing stormwater servitude registered across this property which allows for the proposed routing of the stormwater pipeline through this property.

Proposed routing of treated sewage effluent through the stormwater attenuation dam before release into the stormwater pipeline.

• The impact is positive and of moderate significance.• Although the volumes of treated sewage effluent that will be generated by the development and treated by

the package sewage treatment plant are relatively low, the plan to route the treated sewage effluent through the attenuation dam poses a number of positive benefits including: increased final polishing of treated effluent likely to result in reduced nutrient levels compared to a situation without this step in the process; dilution of treated effluent with freshwater before discharge; a storage facility for treated effluent that can be used to capture and hold effluent from the package sewage treatment plant should there be a problem with the treatment plant s functioning, which if operated properly would significantly reduce the risk of water resource contamination in the event of treatment plant failure / malfunction.

Proposed release of stormwater and treated sewage effluent mix upstream of the Noelle Road culvert, eliminating the need to construct a headwall and outfall structure in the Mphiti River.

• The impact is positive and of moderate significance.• The construction of a new headwall and outfall structure in the Mphiti would have resulted in a number of

negative impacts on the stream bank, and may have created an erosion point in this river. These risks are avoided by discharging the stormwater and treated sewage mix upstream of the culvert under Noelle Rd, which has an existing discharge point into the Mphiti River.

Indirect impacts:

None.

Cumulative impacts:

None.

Alternative A2 (if any)

Alternative A2 involves the construction of a treated sewer effluent pipeline from the package sewage treatment plant, across the drainage line, a pumpstation, a section of pipeline along the north-western boundary of the property, which exits the property and follows the southern boundary of an adjacent property down to the Mphiti River.

Direct impacts:

Positioning of proposed sewerage pipeline across the drainage line, resulting in disturbance to this system and possibly presenting a risk of pipe breakage in the event of a storm and soil erosion in the drainage line.

• The impact is negative and of low significance.• The drainage line is severely degraded due to alien plant infestations. Further to this, the ecological linkage

with the Mphiti River and regional river network has been broken by historical piping of the water flow from the stormwater attenuation dam through the property immediately downstream of the development. Note that a house is also built over the erstwhile drainage line on this adjacent property. As there is a proposal to pipe the stormwater flow from the attenuation dam, the risk of pipe breakage is limited.

Treated sewage effluent is discharged directly into the Mphiti River without final polishing or dilution. • This impact is negative and of moderate significance.• While the package sewage treatment plant is designed to produce treated sewage effluent that meets the

General Limit Value (GLV) standards prescribed by the Department of Water Affairs, the effluent discharged into the Mphiti River will be expected to contain elevated levels of nutrients that could otherwise be reduced by final polishing in the stormwater attenuation dam.

The need for a pumpstation to be constructed and operated to pump the treated sewage effluent off the property, resulting in increased energy usage and increased risk of environmental contamination from pumpstation failure.

• The impact is negative and of moderate significance.• It would be undesirable for the development to operate a pumpstation when an alternative exists to gravity

feed the treated sewage effluent off the property.

The need for construction of a headwall and outfall in the Mphiti River, resulting in stream bank impacts and a possible erosion point.

• This impact is negative and of moderate significance,• The construction of a new headwall and outfall structure in the Mphiti may result in a number of negative

impacts on the stream bank, and may create an erosion point in this river.

The need to run the treated sewage effluent pipeline through a neighbouring property, in addition to the stormwater pipeline through another neighbouring property.

• The impact is negative and of moderate significance.


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• Pipeline bursts and leaks would need to be attended to by the Homeowners Association of Crowhurst. Having pipeline infrastructure on two neighbouring properties when it is possible to combine such pipeline infrastructure in one route alignment is not desirable.

Indirect impacts:

There is no storage facility i.e. stormwater attenuation dam, to contain sub-standard effluent in the event of the package sewage treatment plant failing.

• The impact is negative and of moderate significance.• While the treatment plant is operating as proposed, this impact is negligible. However, in the event of the

treatment plant failing, the significance of this impact is high, as sub-standard treated sewage effluent discharged into the Mphiti River will negatively affect the ecological functioning of downstream aquatic environments.

Cumulative impacts:

None.


The no-go alternative involves not constructing the package sewage treatment plant and associated sewerage pipelines, and involves not constructing the proposed stormwater pipeline from the attenuation dam to the outfall upstream of the Noelle Drive culvert.

Direct and Indirect impacts:

The avoidance of all direct and indirect impacts associated with the proximity of the proposed package sewage treatment plant and associated infrastructure to the drainage line, as well as sewer and stormwater infrastructure located within the drainage line.

• The impact of not constructing the stormwater pipeline are negative and of high significance locally. • The reason for this is that the stormwater overflows from the stormwater attenuation dam would then enter

the existing drainage line and pipeline (which is too small to accommodate the anticipated peak flows from the development) and would be likely to pose a severe threat to the downstream property, which has a house built across the drainage line.

• The impact of not building the package sewage treatment plant and associated sewerage infrastructure is negative and of low significance.

• In this instance the default position the on-site sanitation would be pursued for the development. While this option is feasible, it poses a slightly higher risk alternative in the medium to long term given the poor suitability of some of the erven on the property for on-site sanitation specifically evapotranspiration areas.

• As the major sewerage pipelines (in the areas within close proximity to the drainage line) are for the most part tied to the stormwater infrastructure, the avoided impact of not constructing these is not a relevant consideration in this instance.

Cumulative impacts:

None.


Alternative A1: Alternative A2:The proposed stormwater pipeline is to replace the existing pipeline, largely staying within the existing area of disturbance.

The drainage line is to be rehabilitated to natural coastal / riverine bush following construction.

The proposed stormwater pipeline crossing the drainage line should be tied to the existing fence, as there is an existing area of disturbance.

The drainage line is to be rehabilitated to natural coastal / riverine bush following construction.

2.2. IMPACTS THAT MAY RESULT FROM THE CONSTRUCTION PHASE


List the potential impacts associated with site alternatives that are likely to occur during the construction phase:


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Alternative S1 (preferred site)


Direct impacts:

Construction of the package sewage treatment plant and associated infrastructure resulting in transformation and clearing of indigenous vegetation outside of (but reasonably) close to the drainage line.

• This impact is negative and of low significance.• The site selected for the proposed package sewage treatment plant has already been cleared. Further to

this, there was previously a house with gardens on this site, which was recently demolished. While the construction of the package sewage treatment plant and associated infrastructure will not result in the direct transformation and clearing of indigenous vegetation, it is recommended that remaining indigenous trees adjacent this site are not removed, and additional locally indigenous trees and shrubs are planted around the treatment plant.

Loss of open space as a result of the construction of the package sewage treatment plant.• This impact is negative and of low significance.• This private open space presented limited recreational or ecological value given its previous transformation

(earth platforming, and planting of gardens) and use (a residential homestead was on this site and has recently been demolished).

• The valley area below and to the east of the package sewage treatment plant site is proposed to be zoned for conservation.

Clearing of vegetation during construction of the package sewage treatment plant and associated infrastructure exposes the bare soil to wind scour and stormwater run-off, resulting in accelerated stormwater runoff and soil erosion, and possible deposition of eroded material in drainage line.

• This impact is negative and of low significance.• These construction activities will generally take place on relatively flat platforms, where the risk of erosion

is lower. However, this potential impact can be mitigated through the implementation of the controls relating to stormwater management and prevention of soil erosion contained in the existing EMPr for Crowhurst Estate.

Indirect impacts:

A limited number of temporary employment opportunities will be generated during the construction phase. • This positive impact is likely to be of negligible significance as only a limited number of short-term

opportunities will be created.

Cumulative impacts:

None.


Indirect impacts:

Cumulative impacts:

No-go alternative (compulsory)Direct impacts:

Indirect impacts:

Cumulative impacts:


Alternative S1 Alternative S2Remaining indigenous trees adjacent the site of the package sewage treatment plant are not to be removed, and additional locally indigenous trees and shrubs are to be planted around the treatment plant.

Implementation of the controls relating to stormwater management and prevention of soil erosion contained in the existing EMPr for Crowhurst Estate must be implemented.


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The valley area below and to the east of the package sewage treatment plant site is to be zoned for conservation use.


List the impacts associated with process, technology, layout or other alternatives that are likely to occur during the construction phase (please list impacts associated with each alternative separately):


Alternative A1 involves the construction of a treated sewage effluent pipeline from the package sewage treatment plant to the existing stormwater attenuation dam, and a stormwater pipeline (underground) from this stormwater attenuation dam down the drainage line, into the downstream neighbouring property, and discharging upstream of the culvert under Noelle Drive some 150m downstream of the stormwater dam.

Direct impacts:

Reconstruction / expansion of existing stormwater pipeline within the drainage line, resulting in transformation and clearing of indigenous vegetation.

• This impact is negative and of low significance.• The drainage line is severely degraded due to alien plant infestations. Further to this, the proposed pipeline

will be positioned within the area of disturbance created by the existing pipeline.• However, to mitigate this potential impact, it is recommended that a construction zone is defined within the

drainage line e.g. 1 m on either side of pipeline, and that this area is demarcated using a shade cloth fence to limit the transformation and clearing of indigenous vegetation, and to prevent the accidental spill over of construction activities outside the defined construction zone.

The reconstruction / expansion of the existing stormwater pipeline may result in uncontrolled stormwater runoff and soil erosion due to the relatively steep gradient of the drainage line.

• This impact is negative and of moderate significance.• The eroded material may be deposited on the property below, or possibly however unlikely, in the Mphiti

River. • The significance of this impact can however be reduced through the implementation of the controls relating

to stormwater management and prevention of soil erosion contained in the existing EMPr for Crowhurst Estate.

• Further to this, it is recommended rehabilitation and landscaping should commence immediately after completion of the laying of the proposed pipeline. Roof thatching from the demolished buildings can possibly be used to slow stormwater runoff and promote infiltration.

The reconstruction / expansion of the existing stormwater pipeline through the property below the site may result in dust, noise and visual impacts.

• This impact is negative and of moderate significance.• The intensity of the impacts is relatively high, but the duration of the construction period will be relatively

short. However, the significance of this potential impact can be mitigated through the implementation of the controls relating to dust, noise and visual impacts contained in the existing EMPr for Crowhurst Estate.

• Further to this, it is recommended that a shade cloth screen is erected between construction activities and the main house on the property to control dust and reduce visual impacts.

The reconstruction / expansion of the existing stormwater pipeline through the property below the site may also result in portions of the garden having to be cleared.

• This impact is negative and of low significance.• The new pipeline will follow the alignment of the existing pipeline wherever possible, limiting the size of the

affected area. • To mitigate this potential impact, it is recommended that sections of lawn and plants that have been

removed are set aside, and used for rehabilitation and landscaping upon completion of construction activities.

Indirect impacts:

None.

Cumulative impacts:

None.

Alternative A2

Alternative A2 involves the construction of a treated sewage effluent pipeline from the package sewage treatment plant, across the drainage line, a pumpstation, a section of pipeline along the north-western boundary of the property, which exits the property and follows the southern boundary of an adjacent property down to the Mphiti River.


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Direct impacts:

Construction of proposed sewerage pipeline across the drainage line, resulting in transformation and clearing of indigenous vegetation.

• This impact is negative and of low significance.• The drainage line is severely degraded due to previous transformation, dumping and alien plant

infestations. • However, to mitigate this potential impact, the proposed pipeline will be positioned within the area of

disturbance created by the existing fence. • Further to this, it is recommended that a construction zone is defined within the drainage line e.g. 1 m on

either side of pipeline, and that this area is demarcated using a shade cloth fence to limit the transformation and clearing of indigenous vegetation, and to prevent the accidental spill over of construction activities outside the defined construction zone.

Construction of proposed sewerage pipeline across the drainage line may result in uncontrolled stormwater runoff and soil erosion due to the relatively steep gradient of the drainage line.

• This impact is negative and of moderate significance.• The eroded material may be deposited on the property below, or possibly however unlikely, in the Mphiti

River.• This impact can however be mitigated through the implementation of the controls relating to stormwater

management and prevention of soil erosion contained in the existing EMPr for Crowhurst Estate.• Further to this, it is recommended rehabilitation and landscaping should commence immediately after

completion of the laying of the proposed pipeline. Roof thatching from the demolished buildings can possibly be used to slow stormwater runoff and promote infiltration.

Construction of proposed sewerage pipeline through the property below the site may result in dust, noise and visual impacts.

• This impact is negative and of moderate significance.• The intensity of the impacts is relatively high, but the duration of the construction period will be relatively

short.• However, the significance of this potential impact can be mitigated through the implementation of the

controls relating to dust, noise and visual impacts contained in the existing EMPr for Crowhurst Estate. • Further to this, it is recommended that a shade cloth screen is erected between construction activities and

the houses on the property to control dust and reduce visual impacts.

Construction of proposed sewerage pipeline through the property below the site may also result in portions of the garden having to be cleared.

• This impact is negative and of low significance.• The new pipeline will generally follow the alignment of the existing fence, limiting the size of the affected

area. To mitigate this potential impact, it is recommended that sections of lawn and plants that have been removed are set aside, and used for rehabilitation and landscaping upon completion of construction activities.

Construction of a headwall and outfall in the Mphiti River, resulting in stream bank impacts and a possible erosion point.

• This impact is negative and of moderate significance,• The construction of a new headwall and outfall structure in the Mphiti may result in the disturbance of

sensitive natural environment, removal of indigenous riparian vegetation, and localised soil erosion and sedimentation of aquatic ecosystems.

• Furthermore, it is undesirable to construct hard infrastructure in an area where it may be at risk due to flooding.

Indirect impacts:

None.

Cumulative impacts:

None.


The no-go alternative involves not constructing the package sewage treatment plant and associated sewerage pipelines, and involves not constructing the proposed stormwater pipeline from the attenuation dam to the outfall at the Noelle Drive culvert.

Direct impacts:

The avoidance of any direct and indirect impacts associated with the construction of the proposed sewerage and stormwater infrastructure within sensitive environments. There is limited positive benefit in this as the construction phase poses limited risk / negative impact, which can be adequately managed through the implementation of the


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EMPr for the development.

Indirect impacts:

Opportunity to create a limited number of temporary employment opportunities will not be realised.

Cumulative impacts:

None.


Alternative A1: Alternative A2:The construction zone is to be defined within the drainage line e.g. 1 m on either side of pipeline, and this area is to be demarcated using a shade cloth fence.

Implementation of the controls relating to stormwater management and prevention of soil erosion contained in the existing EMPr for Crowhurst Estate is required.

Rehabilitation and landscaping should commence immediately after completion of the laying of the proposed pipeline.

Roof thatching should be used to slow stormwater runoff and promote infiltration.

Implementation of the controls relating to dust, noise and visual impacts contained in the existing EMPr for Crowhurst Estate are to be implemented.

Shade cloth screen is to be erected between pipeline laying activities and the main house on the property to control dust and reduce visual impacts.

New pipeline should follow the alignment of the existing pipeline wherever possible.

Sections of lawn and plants that have been removed areto be set aside, and used for rehabilitation and landscaping upon completion of construction activities.

The construction zone is to be defined within the drainage line e.g. 1 m on either side of pipeline, and this area is to be demarcated using a shade cloth fence.

Implementation of the controls relating to stormwater management and prevention of soil erosion contained in the existing EMPr for Crowhurst Estate is required.

Rehabilitation and landscaping should commence immediately after completion of the laying of the proposed pipeline.

Roof thatching should be used to slow stormwater runoff and promote infiltration.

Implementation of the controls relating to dust, noise and visual impacts contained in the existing EMPr for Crowhurst Estate.

Shade cloth screen is erected between construction activities and the houses on the property to control dust and reduce visual impacts.

New pipeline should follow the alignment of the existing fence wherever possible.

Sections of lawn and plants that have been removed are to be set aside, and used for rehabilitation and landscaping upon completion of construction activities.

2.3. IMPACTS THAT MAY RESULT FROM THE OPERATIONAL PHASE


List the potential impacts associated with site alternatives that are likely to occur during the operational phase:

Alternative S1 (preferred alternative)


Direct impacts:

Potential odour and noise nuisance from the proposed package sewage treatment plant.• This impact is negative and of low significance.• The package sewage treatment plant has been sited adjacent to the property boundary in the west corner

of the Crowhurst Estate. To the west of the site is Ashley Drive, a major road thoroughfare, and to the northis a private residential property (80m). To the south and east are residential properties falling within Crowhurst Estate (50m).

• The residential properties nearest to the package sewage treatment plant and therefore most affected by odour or noise impacts would be those within Crowhurst Estate. The incentive to ensure that the works is operating effectively with minimum impacts is therefore high for the Homeowners Association.

• The nearest neighbouring private house is 80m from the package sewage treatment plant site. This house could be affected by noise and / or odour impacts from the package sewage treatment plant if it were not functioning correctly. This impact would be of a similar magnitude to other houses within Crowhurst Estate


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in close proximity to the treatment plant.

Failure of the package sewage treatment plant and associated water resource impacts.• This impact would be negative and of low significance with Layout Alternative A1 implemented, and of

moderate significance with layout Alternative A2 implemented.• The construction and operation of the package sewage treatment plant in the proposed position creates the

opportunity to utilise the stormwater attenuation dam as a back-up facility to capture and temporarily store any untreated effluent that may spill from or overflow from the package sewage treatment plant for any reason. This would significantly mitigate negative impacts on the receiving environment if the effluent were either removed by honeysucker for disposal at another wastewater treatment works, or pumped back to the treatment plant when functional for re-treatment.

• To mitigate the likelihood of the package sewage treatment plant failing, it is recommended that daily inspections are undertaken to ensure that the pumps are working and RBCs are rotating.

• Further to this, suitably qualified specialists should be appointed to operate and maintain the package treatment plant. In the event that treatment plant fails, the outfall from the stormwater attenuation dam into the pipeline down to the Mphiti River should be closed immediately to contain potential impacts onsite.

Water quality impacts in the Mphiti River from the release of treated effluent from the package sewage treatment plant.

• This impact is likely to be of limited significance, but is not assessed in detail here. The Applicant s process of engagement with the Department of Water Affairs in applying for registration and licensing of the treatment plant will evaluate this impact and required mitigation measures / controls in detail.

Indirect impacts:

None.

Cumulative impacts:

None.


Indirect impacts:

Cumulative impacts:


Indirect impacts:

Cumulative impacts:


Alternative S1 Alternative S2It is recommended that a vegetative buffer be retained / created around the package sewage treatment plant site to limit odour and noise effects on all houses in close proximity to thetreatment plant including those both on and off the Crowhurst Estate property.

The package sewage treatment plant must be operated by a suitably qualified and experienced company, all equipment must be regularly serviced, and the Homeowners Association must have a response plan should the treatment plant overflow, spill, cause odour or noise nuisance. Daily inspections must be conducted.


List the impacts associated with process, technology, layout or other alternatives that are likely to occur during the operational phase (please list impacts associated with each alternative separately):


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Alternative A1 involves the construction of a treated sewage effluent pipeline from the package sewage treatment plant to the existing stormwater attenuation dam, and a pipeline (underground) from this stormwater attenuation dam down the drainage line, into the downstream neighbouring property, and discharging upstream of the culvert under Noelle Drive some 150m downstream of the stormwater dam.

Direct impacts:

Increase in peak stormwater discharges into Mphiti River due to increased hardened surfaces at Crowhurst Estate, as well as outflows from the package sewage treatment plant, resulting in river scour or associated impacts.

• This impact is negative and of low significance.• Discharge from the estate will only increase by approximately 1% from 137 per second (current

stormwater peak flows) to 140 per second (including stormwater and treated sewage effluent).• Stormwater attenuation measures on the property are required to ensure that peak stormwater flows after

construction of the estate do not exceed pre-development peaks.• In terms of the overall size of the Mphiti River catchment, the contribution to the peak flows in the Mphiti

from the Crowhurst development are likely to be fairly small. However, on-site attenuation is important to limit the potential for cumulative stormwater peak elevation in the catchment from various developments taking place.

Increase in peak stormwater discharges into grassed open channel between culvert below Noelle Drive and the Mphiti River due to increased hardened surfaces at Crowhurst Estate, as well as outflows from the package sewage treatment plant, resulting in increased scouring of the channel.

• This impact is negative and of moderate significance.• Discharge from the estate will only increase by approximately 1% from 137 per second (current

stormwater peak flows) to 140 per second (including stormwater and treated sewage effluent).• Stormwater attenuation measures on the property are required to ensure that peak stormwater flows after

construction of the estate do not exceed pre-development peaks.• This channel is already incised due to current stormwater outflows from Crowhurst Estate, and will continue

to erode, particularly with increased flows, however negligible these increases may be. • This grassed open channel will therefore need to be stabilised through the widening and shallowing of the

profile of the existing channel, the revegetation of the channel using appropriate indigenous vegetation, and the stabilisation of potential erosion points using soft infrastructure, such as rock pack (rather than gabion baskets), to prevent future erosion.

Water resource impact risks under conditions of package sewage treatment plant failure.• This impact is negative and of low significance.• Owing to the fact that this alternative includes routing the treated sewage effluent through the stormwater

attenuation dam, the opportunity exists to utilise the stormwater attenuation dam as a back-up facility to capture and temporarily store any untreated effluent that may spill from or overflow from the package sewage treatment plant for any reason. This would significantly mitigate negative impacts on the receiving environment if the treated sewage effluent were either removed by honeysucker for disposal at another wastewater treatment works, or pumped back to the package sewage treatment plant when functional for re-treatment.

Indirect impacts:

Discharge pipeline checking and maintenance can take place along a single pipeline route from the stormwater attenuation dam to the outfall at Noelle Drive. The pipeline crosses one private property adjacent the site.

Cumulative impacts:

None.Alternative A2


Direct impacts:

This layout alternative requires a relatively large pump to pump treated sewage across the site, and down to the Mphiti River. In the event that this pump fails, the impact can be significant, as it may result in the package sewage treatment plant or pumpstation overflowing, spilling down into the drainage line. To mitigate this impact, a standby pump should be fitted, as well as a backup power source.

Water resource impact risks under conditions of package sewage treatment plant failure.• This impact is negative and of moderate significance.• Owing to the fact that this alternative does not include routing the treated sewage effluent through the

stormwater attenuation dam, there is no opportunity to capture and temporarily store any sub-standardsewage effluent that may spill from or overflow from the treatment plant for any reason.


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Indirect impacts:

Discharge pipeline checking and maintenance has to take place along two separate pipeline routes: one from the stormwater attenuation dam to the outfall at Noelle Drive; and one from the package sewage treatment plant to the outfall at the Mphiti River. The pipelines cross two different private properties adjacent the site, creating more risk and institutional burden than in option A1.

Cumulative impacts:

None.


The no-go alternative involves not constructing the package sewage treatment plant and associated sewerage pipelines, and involves not constructing the proposed stormwater pipeline from the attenuation dam to the outfall at the Noelle Drive culvert.

Direct impacts:

The avoidance of any direct and indirect impacts associated with the operation of the proposed sewerage and stormwater infrastructure within sensitive environments.

Potential risk to natural environment may be increased by the on-site sanitation systems.• Negative impact, medium significance.• On-site sanitation may work well for some of the erven within the development, but for the erven on the

north-western portion, there isn t sufficient space to achieve optimum evapotranspiration on each erf, given the steepness of these sites. As these sites have steep embankments. It is possible that poorly assimilated soakaway water would seep from the embankments and cause surface and ground water pollution.

Indirect impacts:

Opportunity to create a limited number of permanent employment opportunities will not be realised.

Cumulative impacts:

Avoidance of the proliferation of small package sewage treatment plants in the outer west area of the eThekwini Municipal Area.


Alternative A1 Alternative A2Stormwater management plan for Crowhurst Estate must ensure that adequate attenuation is undertaken on the property to minimise the risk of contributing to elevated peak flows in the Mphiti River (and associated river scouring and erosion).

The stormwater attenuation dam must have equipment installed that allows the overflow from the dam into the stormwater pipeline to be shut off allowing temporary capture and storage of any overflow from the package sewage treatment plant should it malfunction. Access to the stormwater attenuation pond by a honeysucker vehicle must be possible in terms of the Estate roads design, and / or portable pumps must be available to pump stored effluent back to the treatment plant for re-treatment as necessary.

A standby pump should be fitted to the pumpstation, as well as a backup power source.

2.4. IMPACTS THAT MAY RESULT FROM THE DECOMISSIONING OR CLOSURE PHASE

There is no planned decommissioning or closure phase.


List the potential impacts associated with site alternatives that are likely to occur during the decommissioning or closure phase:


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Alternative S1 (preferred alternative)Direct impacts:

Indirect impacts:

Cumulative impacts:

Alternative S2Direct impacts:

Indirect impacts:

Cumulative impacts:


Indirect impacts:

Cumulative impacts:


Alternative S1 Alternative S2


List the impacts associated with process, technology, layout or other alternatives that are likely to occur during the decommissioning or closure phase (please list impacts associated with each alternative separately):

Alternative A1 (preferred alternative)Direct impacts:

Indirect impacts:

Cumulative impacts:

Alternative A2Direct impacts:

Indirect impacts:

Cumulative impacts:


Indirect impacts:

Cumulative impacts:


Alternative A1 Alternative A2

2.5. PROPOSED MONITORING AND AUDITING

For each phase of the project and for each alternative, please indicate how identified impacts and mitigation will be monitored and/or audited.


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Alternative S1 (preferred site) Alternative S2

Construction PhaseThe conditions contained in the EMPr for Crowhurst Estate must be adhered to.

An independent ECO is to be appointed during construction phase to monitor and report on compliance with the conditions contained in the EMPr.

Monthly audits of construction activities to be undertaken by ECO and audit reports submitted to DAEA compliance department.

Operational PhaseCompliance with the controls of the EMPr must be included in the contract of the engineer appointed to operate and manage the package sewage treatment plant. Compliance auditing in respect of effluent quality must meet the requirements specified by the Department of Water Affairs.

Alternative A1 (preferred alternative) Alternative A2



Monthly audits of construction activities to be undertaken by ECO and audit reports submitted to DAEA compliance department.

Operational PhasePipelines should be regularly checked for blockages, leaks or erosion (at outfalls etc.).

The stormwater attenuation dam must be maintained such that it can function as a stormwater attenuation feature and temporary storage feature for overflows / spills from the package sewage treatment plant this includes keeping sufficient freeboard in the dam for such storage.



Monthly audits of construction activities to be undertaken by ECO and audit reports submitted to DAEAcompliance department.

Operational PhasePipelines should be regularly checked for blockages, leaks or erosion (at outfalls etc.).

The pumpstation should be regularly checked and equipment serviced.

A spill management plan must be prepared for the pumpstation.

3. ENVIRONMENTAL IMPACT STATEMENT

Taking the assessment of potential impacts into account, please provide an environmental impact statement that summarises the impact that the proposed activity and its alternatives may have on the environment after the management and mitigation of impacts have been taken into account, with specific reference to types of impact, duration of impacts, likelihood of potential impacts actually occurring and the significance of impacts.

Alternative S1 (preferred site)

Crowhurst Estate is a residential development located in Everton (Durban), comprising 12 five-bedroom units and associated infrastructure (i.e. roads, water, stormwater etc.) aimed at servicing the high-income housing market.The total area of the development site is 2.6 ha, and includes a non-perennial drainage line in the western portion.

It is proposed that the package sewage treatment plant will be located on the existing earth platform in the westerncorner of the site, adjacent the non-perennial drainage line. As such, the proposed package sewage treatment plant and associated sewerage pipelines are located within 32 metres of the drainage line.

The site proposed for construction of the package sewage treatment plant was selected as it is the lowest point on the property, thus allowing raw sewage to be gravity fed from the 12 units down to this point for treatment. This location is optimal from an engineering design point of view, as it negates the need for pumpstations to be


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constructed to pump the raw sewage to the point of treatment. Pumpstations are energy intensive and are often points of sewage spillage as a result of pump failure and other problems in the pumping system.

No other site options for the package sewage treatment plant are considered in this report, as there are no other vacant areas on the property that are below the majority of the residential erven, large enough to accommodate the treatment plant, and potentially accessible by vehicle (note that the northern part of the property is oversteep).

Site Alternative 1 (the preferred site alternative) is therefore the proposed location of the package sewage treatment plant on an existing platform, within 32m of the drainage line, in the western corner of the Crowhurst Estate development property.

The potential direct, indirect and cumulative impacts associated with the preferred site alternative, the duration of these impacts, the likelihood of the impacts occurring and the significance of such impacts with and without recommended mitigation measures in place are detailed below:

Impact Duration of Impact

Likelihood of Occurrence

Significance without mitigation

Significance with mitigation

Planning Phase ImpactsPositioning of the package sewage treatment plant in close proximity to the drainage line resulting in construction needing to happen in a sensitive environment.

Long High Negative - Low Negative - Low

Positioning of the package sewage treatment plant in the proposed position where all sewage generated on the site can be gravity fed to this point, thereby eliminating the need for pumping of sewage across the site.

Long High Positive - Moderate N/A

Contribution to a proliferation of package sewage treatment plants in the outer west area of eThekwini Municipality, resulting in heightened risk to water resources.


Construction Phase ImpactsConstruction of the package sewage treatment plant and associated infrastructure resulting in transformation and clearing of indigenous vegetation outside of (but reasonably) close to the drainage line.

Short Medium Negative - Low Negative - Low

Loss of open space as a result of the construction of the package sewage treatment plant.


Clearing of vegetation during construction of the package sewage treatment plant and associated infrastructure exposes the bare soil to wind scour and stormwater run-off, resulting in accelerated stormwater runoff and soil erosion, and possible deposition of eroded material in drainage line.


A limited number of temporary employment opportunities will be generated during the construction phase.

Short High Positive - Low N/A


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Operational Phase ImpactsPotential odour and noise nuisance from the proposed package sewage treatment plant.


Failure of the package sewage treatment plant and associated water resource impacts.

Short Low Negative - Moderate Negative - Low

Water quality impacts in the Mphiti River from the release of treated sewage effluent from the package sewage treatment plant.

Long Low Negative - Low Negative - Low

In accordance with the above assessment, and the considerations in this Basic Assessment Report, the proposed location of the package sewage treatment plant and associated infrastructure in a sensitive natural environment (i.e. within 32m of a watercourse or drainage line) is not deemed to present significant negative environmental issues or impacts. The following factors are key considerations in this assessment:

1. The drainage line that is affected by the proposed sewerage infrastructure and package sewage treatment plant is highly degraded, having previously been transformed from a natural state by earthworks platforming (to create the site where the package sewage treatment plant is proposed, and which until recently was the site of a residential building), extensive dumping of garden and other domestic refuse and builders rubble in the drainage line, alien plant infestations and garden plants. The receiving environment is therefore far from being in a pristine state and presents a low functionality

from an ecosystems perspective.

2. The site selected for the package sewage treatment plant is an existing earth platform. Limited earthworks are needed to construct this facility. Trenching will however be required for the construction of sewerage pipelines.

3. The package sewage treatment plant site is optimally located from an engineering point of view, being below all the units on the property, thus allowing sewage to be gravity fed to this point and eliminating the need for pumpstations.

4. The steeply incised topography of the drainage line is such that the site of the package sewage treatment plant is elevated considerably above the valley bottom despite its apparent close proximity in horizontal distance. The treatment plant therefore would be unlikely to be flooded or affected by stormwater in the drainage line, and is set far enough back from and above the valley bottom such that indigenous valley / riparian vegetation may be re-established between the treatment plant and the drainage line.

5. The houses most likely to be affected by odour and noise impacts associated with operating a package sewage treatment plant on the preferred site, are those located within the Crowhurst Estate development and closest to the treatment plant site. This will result in a positive incentive amongst the Homeowners to operate the treatment plant effectively and properly so as to avoid such impacts on their own homeowners. There is a private house on the property neighbouring Crowhurst on the north-western boundary that may also be affected by such impacts however this impact would be unlikely to be significant, or frequent, or of long duration.

As such, it is concluded that the preferred site alternative for the package sewage treatment plant and immediately associated sewerage infrastructure that falls within 32m of the drainage line, are appropriately positioned and do not pose a significant environmental threat in this location.

Alternative S2


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For the preferred alternative, it is proposed that treated sewage effluent will be fed via gravity into the upper tier of the stormwater attenuation dam for final polishing and dilution. Overflows from the stormwater attenuation dam(comprising treated sewage effluent and stormwater) will then drain into an underground stormwater pipeline that runs along the drainage line on the Crowhurst property, and through one downstream neighbouring property,ultimately discharging upstream of a culvert under Noelle Drive, which drains into the Mphiti River. It is proposed that this pipeline will replace an existing stormwater pipeline which runs along the surface in the same route alignment.

The potential direct, indirect and cumulative impacts associated with the preferred layout alternative, the duration of these impacts, the likelihood of the impacts occurring and the significance of such impacts with and without recommended mitigation measures in place are detailed below:





Planning Phase ImpactsProposed construction of a stormwater (and treated sewageeffluent transfer) pipeline (rather than an open channel for example) within the drainage line from the stormwater attenuation dam to the Noelle Drive culvert, resulting in transformation of the watercourse and clearing of natural vegetation.


Proposed construction of a stormwater (and treated sewage effluent transfer) pipeline through the private property adjacent to and downstream of the development property, resulting in disturbance to the neighbour sproperty.


Proposed routing of treated sewage effluent through the stormwater attenuation dam before release into the stormwater pipeline, improving effluent quality and providing a buffer for overflows / spills from the package sewage treatment plant.


Proposed release of stormwater and treated sewage effluent mix upstream of the Noelle Driveculvert, eliminating the need to construct a headwall and outfall structure in the Mphiti River.


Construction Phase ImpactsReconstruction / expansion of existing stormwater pipeline within the drainage line, resulting in transformation and clearing of indigenous vegetation.

Short High Negative - Low Negative - Low

The reconstruction / expansion of the existing stormwater pipeline may result in uncontrolled stormwater runoff and soil erosion due to the relatively steep gradient of the drainage line.

Short Medium Negative - Moderate Negative - Low

The reconstruction / expansion of the existing stormwater pipeline Short High Negative - Moderate Negative - Low


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through the property below the site may result in dust, noise and visual impacts. The reconstruction / expansion of the existing stormwater pipeline through the property below the site may also result in portions of the garden having to be cleared.


Increased turbidity and sedimentation in the Mphiti River as a result of sewerage and stormwater construction activities at Crowhurst Estate.

Short Low Negative - Low Negative - Low

Operational Phase ImpactsIncrease in peak stormwater discharges into Mphiti River due to increased hardened surfaces at Crowhurst Estate, as well as outflows from the package sewage treatment plant, resulting in river scour or associated impacts.


Increase in peak stormwater discharges into grassed open channel between culvert underneath Noelle Drive and the Mphiti River due to increased hardened surfaces at Crowhurst Estate, as well as outflows from the package sewage treatment plant, resulting in increased scouring of the channel.

Long Medium Negative - Moderate Negative - Low

Water resource impact risks under conditions of package sewage treatment plant failure.

Short Low Negative - Low Negative - Low

Discharge pipeline checking andmaintenance can take place along a single pipeline route from the stormwater attenuation dam to the outfall at Noelle Drive. The pipeline crosses one private property adjacent the site.

Long High Positive - Low N/A

In accordance with the above assessment, and the considerations in this Basic Assessment Report, the proposed layout (A1) of stormwater and sewerage infrastructure in a sensitive natural environment (i.e. within 32m of a watercourse or drainage line) is not deemed to present significant negative environmental issues or impacts. The following factors are key considerations in this assessment:

1. The drainage line that is affected by the proposed sewerage / stormwater pipelines is highly degraded, having previously been transformed from a natural state by earthworks platforming, extensive dumping of garden and other domestic refuse and builders rubble in the drainage line, alien plant infestations and garden plants. The receiving environment is therefore far from being in a pristine state and presents a low functionality from an ecosystems perspective.

2. The proposed pipeline will be buried underground for the most part, permitting re-establishment of natural vegetation in the valley-line post construction.

3. The upgrading of the stormwater pipeline will address to some extent an existing issue, which is that of stormwater damage on the downstream neighbouring property, where a house has been built across the drainage line.

4. The combination of stormwater and treated sewage effluent in one pipeline, limits the need for construction of multiple pipelines and the associated construction disturbance and maintenance


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requirements. This is considered to be a positive design feature.

5. The proposed use of the stormwater attenuation dam for final polishing and dilution of the treated sewage effluent is considered to be a positive design feature. In addition, this dam offers the opportunity to capture and temporarily store untreated or sub-standard sewage effluent in the instance that the package sewage treatment plant was to fail. This is considered to be a highly advantageous design feature.

6. The proposed discharge of the stormwater and treated sewage effluent mix immediately upstream of the culvert under Noelle Drive is considered to be a positive design feature that eliminates the need to construct a headwall and outfall point into the Mphiti River, with associated stream bank stability and erosion issues. The V-drain between this culvert and the Mphiti River will, however need to be stabilised using low key channel stabilisation methods.

As such, it is concluded that the preferred layout alternative for the stormwater and treated sewage effluent transfer from the stormwater attenuation dam to the discharge point at the culvert under Noelle Drive, and the point from the culvert to the Mphiti River, that fall within 32m of the drainage line / Mphiti River, are appropriately positioned and do not pose a significant environmental threat in this location.

Alternative A2


The potential direct, indirect and cumulative impacts associated with the layout alternative 2, the duration of these impacts, the likelihood of the impacts occurring and the significance of such impacts with and without recommended mitigation measures in place are detailed below:





Planning Phase ImpactsPositioning of proposed seweragepipeline across the drainage line, resulting in disturbance to this system and possible presenting a risk of pipe breakage in the event of a storm and soil erosion in the drainage line.


Treated sewage effluent is discharged directly into the Mphiti River without final polishing and dilution.


The need for a pumpstation to be constructed and operated to pump the treated sewage effluent off the property, resulting in increased energy usage and increased risk of environmental contamination from pumpstation failure.

Long High Negative - Moderate Negative - Moderate

The need for construction of a headwall and outfall in the Mphiti River, resulting in stream bank impacts and a possible erosion point.


The need to run the treated sewage effluent pipeline through a neighbouring property, in addition to the stormwater pipeline through



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another neighbouring property.There is no storage facility i.e. stormwater attenuation dam, to contain sub-standard sewage effluent in the event of the package sewage treatment plant failing.

Long Low Negative - Moderate Negative - Moderate

Construction Phase ImpactsConstruction of proposed sewerage pipeline across the drainage line, resulting in transformation and clearing of indigenous vegetation.


Construction of proposed sewerage pipeline through the property below the site may also result in portions of the garden having to be cleared.

Short High Negative - Moderate Negative - Low

Construction of proposed sewerage pipeline through the property below the site may result in dust, noise and visual impacts.

Short High Negative - Moderate Negative - Low

Construction of proposed sewerage pipeline across the drainage line may result in uncontrolled stormwater runoff and soil erosion due to the relatively steep gradient of the drainage line.


Construction of a headwall and outfall in the Mphiti River, resulting in stream bank impacts and a possible erosion point.


Operational Phase ImpactsThis layout alternative requires a relatively large pump to pump treated sewage effluent across the site, and down to the Mphiti River. In the event that this pump fails, the impact can be significant, as it may result in the package sewagetreatment plant or pumpstation overflowing, spilling down into the drainage line.

Short Medium Negative - Moderate Negative - Low

Discharge pipeline checking and maintenance has to take place along two separate pipeline routes: one from the stormwater attenuation dam to the outfall at Noelle Drive; and one from the package sewage treatment plant to the outfall at the Mphiti River. The pipelines cross two different private properties adjacent the site, creating more risk and institutional burden than in option A1.


In accordance with the above assessment, and the considerations in this Basic Assessment Report, the proposed layout (A2) of stormwater and sewerage infrastructure in a sensitive natural environment (i.e. within 32m of a watercourse or drainage line) is not recommended as the best option for approval, owing to the following key reasons:

1. The proposed routing of the pipeline transferring treated sewage effluent from the package sewage


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treatment plant by-passes the stormwater attenuation dam (thereby not benefitting from the final effluent polishing and dilution that is achieved in layout A1), requires a pumpstation to pump the treated sewage effluent across the site (posing elevated levels of environmental risk due to spillage / failure of the pumpstation), and is not combined with the stormwater pipeline (meaning that there are two pipelines that have to be constructed and maintained, with implications for obtaining access onto two other private properties to do so).

2. A new headwall and outfall point would have to be constructed to discharge the treated effluent into the Mphiti River, which is not the case with Alternative A1.

As such, layout alternative A2 is not recommended as layout A1 presents a lower impact alternative.


The no-go alternative would involve not planning for the construction of the package sewage treatment plant, and not constructing or operating such. The implication would be that the development was constructed as already approved and was serviced with on-site sanitation involving septic tanks and soakaways.

Similarly, the no-go development alternative would involve not constructing the stormwater pipeline from the attenuation dam to the discharge point at or near the Mphiti River, requiring continued use of the existing surface stormwater pipeline (already in place) and surface flows in the drainage line.





Planning Phase ImpactsNo loss of open space in the western corner of the site this remains undeveloped.


Potential to achieve the highest and best land use potential may be limited by the fact that unit sizes are curtailed by the on-site sanitation capability of each erf within the estate.

Long Medium Negative - Low Negative - Low

Potential risk to natural environment may be increased by the on-site sanitation systems.

Long Medium Negative - Moderate Negative - Moderate

The avoidance of all direct and indirect impacts associated with the proximity of the proposed package sewage treatment plant and associated infrastructure to the drainage line, as well as sewerage and stormwater infrastructure located within the drainage line.

Long High

Negative High (not constructing

stormwater pipeline)

Negative Low (not constructing sewerage

infrastructure & treatment plant)

Negative High

Negative - Low

Construction Phase ImpactsThe avoidance of any direct and indirect impacts associated with the construction of the proposed sewerage and stormwater infrastructure within sensitive environments. There is limited positive benefit in this as the construction phase poses limited risk / negative impact, which can be adequately managed through the implementation of the EMPr for the development.

Short High Negative - Low Negative - Low

Opportunity to create a limited number of temporary employment Short High Negative - Low Negative - Low


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opportunities will not be realised. Operational Phase ImpactsThe avoidance of any direct and indirect impacts associated with the operation of the proposed sewerage and stormwater infrastructure within sensitive environments.

Long High

Negative High (not constructing

stormwater pipeline)

Negative Low (not constructing sewerage

infrastructure & treatment plant)

Negative High

Negative - Low

Potential risk to natural environment may be increased by the on-site sanitation systems.

Long Medium Negative - Moderate Negative - Moderate

Opportunity to create a limited number of permanent employment opportunities will not be realised.


Avoidance of the proliferation of small package sewage treatment plants in the outer west area of the eThekwini Municipal Area.


In accordance with the above assessment, and the considerations in this Basic Assessment Report, the no-go alternative is not recommended, owing to the following key reasons:

1. The proposed package sewage treatment plant, being of relatively small size and throughput, and being located in an area that is deemed not to pose a significant environmental risk, is not likely to result in significant negative impacts provided that it is properly operated and maintained, and that layout alternative A1 is implemented for the outflow infrastructure.

2. Should the no-go option be approved, the default position will be for Crowhurst Estate to be developed with on-site sanitation systems (as is already approved by the eThekwini Municipality), which poses a higher environmental risk alternative than the proposed septic tanks and package sewage treatment plant and associated infrastructure given the unsuitable nature of some of the erven for evapotranspiration areas to be accommodated on flat land a suitable distance set back from the drainage line.

3. The existing surface stormwater pipeline in the drainage line is old, blocked and leaking i.e. inadequately servicing the existing site. This situation has created elevated levels of risk for the adjacent downstream property owner where a building has been constructed across the drainage line, and which has suffered stormwater damage in the past. The proposed construction / upgrading of the stormwater pipeline in the drainage line is deemed to be a positive intervention that will meet the stormwater discharge needs of Crowhurst, while addressing this existing problem of stormwater flows experienced by the neighbour. Further to this, the upgrading of the existing pipeline can be seen as making best use of the stormwater servitude that is registered across this property.

As such, the no-go development option is not recommended as the best development option.


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SECTION F. RECOMMENDATION OF EAP

Is the information contained in this report and the documentation attached hereto in the view of the EAP sufficient to make a decision in respect of this report?

YES

If NO , please contact the KZN Department of Agriculture & Environmental Affairs regarding the further requirements for your report.

If YES , please attach the draft EMPr as Appendix F to this report and list any recommended conditions, including mitigation measures that should be considered for inclusion in any authorisation that may be granted by the competent authority in respect of the application:

It is recommended that the Application for Environmental Authorisation be Approved, including preferred Site Alternative (S1), and the preferred Layout Alternative (A1), subject to the following conditions:

Recommendations to mitigate potential direct and indirect impacts associated with the preferred site alternative:

1. Remaining indigenous trees adjacent site of the proposed package sewage treatment plant are not to be removed, and additional locally indigenous trees and shrubs are to be planted around the package sewage treatment plant for noise and odour screening.

2. Implementation of the controls relating to stormwater management and prevention of soil erosion contained in the EMPr for Crowhurst Estate is required.

3. The valley area below and to the east of the package sewage treatment plant site is to be zoned for conservation use.

4. The package sewage treatment plant must be operated by a suitably qualified and experienced company, all equipment must be regularly serviced, and the Homeowners Association must have a response plan should the plant overflow, spill, cause odour or noise nuisance. Daily inspections must be conducted.

Recommendations to mitigate potential direct and indirect impacts associated with the preferred layout alternative:

1. The construction zone is to be defined within the drainage line e.g. 1 m on either side of pipeline, and this area is demarcated using a shade cloth fence. The proposed pipeline is to replace the existing pipeline, largely staying within the existing area of disturbance

2. Implementation of the controls relating to stormwater management and prevention of soil erosion contained in the EMPr for Crowhurst Estate is required.

3. Rehabilitation and landscaping should commence immediately after completion of the laying of the proposed pipeline. The drainage line is to be rehabilitated to natural coastal / riverine bush following construction.

4. Roof thatching (available on the site) should be used to slow stormwater runoff and promote infiltration.


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5. Implementation of the controls relating to dust, noise and visual impacts contained in the EMPr for Crowhurst Estate must be implemented.

6. Shade cloth screen is to be erected between construction activities and the main house on the adjacent property to control dust and reduce visual impacts during laying of the pipeline.

7. The new stormwater / treated sewage effluent pipeline should follow the alignment of the existing surface pipeline wherever possible.

8. Sections of lawn and plants that have been removed must be set aside, and used for rehabilitation and landscaping upon completion of construction activities.

9. The stormwater management plan for Crowhurst Estate must ensure that adequate attenuation is undertaken on the property to minimise the risk of contributing to elevated peak flows in the Mphiti River (and associated river scouring and erosion).

10. The stormwater attenuation dam must have equipment installed that allows the overflow from the dam into the stormwater pipeline to be shut off allowing temporary capture and storage of any overflow from the package sewage treatment plant should it malfunction. Access to the stormwater attenuation pond by a honeysucker vehicle must be possible in terms of the Estate roads design, and / or portable pumps must be available to pump stored effluent back to the treatment plant for re-treatment as necessary.

11. The grassed V-drain between the culvert underneath Noelle Drive and the Mphiti River must be stabilised. This should include widening of the channel and reshaping of the embankments (i.e. shallowing the profile), planting with suitable indigenous vegetation, and to use low key channel stabilisation infrastructure, such as rock pack, at potential erosion points.

Date post:	27-Mar-2018
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