ADDENDUM NO. 5 (POST BID) -...

ADDENDUM NO. 5(POST BID)

RE: Phase 2 Improvements DATE: May 16, 2017New Administration BuildingWernle Youth & Family Treatment Center2000 Wernle RoadRichmond, Indiana

TO: All Bidders

Gentlemen:

This Addendum shall hereby be and become a part of the Contract Documents the same as iforiginally bound thereto.

The following clarifications, amendments, additions, revisions, changes, and modifications changethe original Contract Documents only in the amount and to the extent hereinafter specified in thisAddendum.

ITEM NO. 1: SUPPLEMENTAL INFORMATION

A. Included for reference is the Stormwater Drainage Report, dated 9/22/16.

ITEM NO. 2: CLARIFICATION

A. Owner to provide data cabling and terminations. Contractor to provide conduit and backboxes as indicated in the drawings.

ITEM NO. 3: PROJECT MANUAL; SECTION 08710 DOOR HARDWARE

A. Delete paragraph B.6.d. and substitute the following:

“d. Provide Schlage Primus #P04443, 6-pin, full size interchangeable cores, keyed tothe existing system.”

B. At all Hardware Groups where it occurs, delete FSIC Conventional Cylinder #26-091 andsubstitute with #20-763.

C. At all Hardware Groups where it occurs, delete FSIC Conventional Cylinder #20-057 andsubstitute with #20-757.

D. At the following seventeen (17) doors, Owner shall furnish closers for Contractor to install:

101A 101B 114A 114B 114C

116 118 119 120 121

130 131 133 134 201A

201B 228

ADDENDUM NO. 5 (POST BID) -2- May 16, 2017

ITEM NO. 4: DRAWING SHEET C2.0

A. Delete drawing C2.0 and substitute attached drawing C2.0, dated 9/22/16.

ITEM NO. 5: DRAWING SHEET C5.0

A. Delete drawing C5.0 and substitute attached drawing C5.0, dated 9/22/16.

ITEM NO. 6: DRAWING SHEET CE1.0

A. Install underground conduit and wiring to the water meter vault. Install one (1) GFCI outletwith weatherproof cover and box within the water meter vault.

ITEM NO. 7: DRAWING SHEET E6.2

A. Delete the Data Cable Specifications in its entirety, without substitutions.

END OF ADDENDUM NO. 5 (POST BID)

Stormwater Drainage Report

for:

Wernle Administration Building

2000 Wernle Road

Richmond, Indiana

Prepared by:

Patrick S. Brown, ASLA, LEED-AP

Registered Landscape Architect

September 22, 2016

Storm Drainage Report for: September 22, 2016 Wernle Administration Building Page 2

Contents

Project Description

Design Requirements

Existing Conditions

Stormwater Analysis

Pre-Development Watershed

Post Development Watershed

2-Year Pre-Development Runoff

10-Year Pre-Development Runoff

10-Year Post Development Runoff

100-Year Post Development Runoff

Detention Basin Design

Outlet Pipe Design

Site Grading Plan Revisions

Site Details Revisions

Post Construction Stormwater Management Plan

Attachments

USGS Richmond Quadrangle Map

Topographical Survey

Pre-Development Watershed Limits

Post Development Watershed Limits

Rainfall Frequency Atlas of the Midwest

2-Year Pre-Development Runoff Calculations

10-Year Pre-Development Runoff Calculations

10-Year Post Development Runoff Calculations

100-Year Post Development Runoff Calculations

Detention Basin Design Calculations

Outlet Pipe Design Calculations

Chart for Flow for Circular Pipes Flowing Full


Project Description

This report has been prepared in conjunction with a project for the Wernle Youth & Family

Treatment Center for a construction of a new 2-level administration building and associated site

improvements. The project site is located on the southeastern portion of the campus adjacent

to Wernle Road. See Attachments for USGS Quadrangle Map, topographical survey for project

site location.

The purpose of this report is to analyze the stormwater runoff generated by the proposed

improvements and its potential affect on the existing site and stormwater facilities. The

proposed project consists of a 6,600 square foot building, parking and walkways.

The Richmond Sanitary District regulations states the discharge rates from the proposed

improvements will be reduced to the peak discharge rates equal to or less than the

undeveloped peak discharge rates for a 10-year storm event.

The existing stormwater runoff currently sheet flows across open lawn, grass and lightly

wooded area with an average slope 6%. Stormwater runoff is directed to the roadway swale,

flowing east, along Wernle Road.

Design Requirements

In accordance with the Richmond Sanitary District the storage volume required for new

improvements shall control the post-development of a 100-year storm. Detention areas shall

have an outlet structure which will discharge no more flow than the pre-development 10-year

storm. The outlet structure will consist of a pre-developed 2-year storm outlet to retain the

lower flows of the 2 to 10 year storm in the staged detention area.

Existing Conditions

The proposed project site sits on the southeast portion of the overall campus. The entire

campus is a rolling terrain with multiple watersheds. The existing project site is gently sloping

west to east with an estimated relief of approximately ten (10) feet. Drainage is primarily along

the ground surface into low lying areas and drainage swales. The project site is not located

within the FEMA 100-year flood plain and no regulated wetlands are located in the vicinity of

the project site.

According to the Soil Survey of Wayne County, Indiana published by the United States

Department of Agriculture Soil Conservation Service, the majority of the soils covering this site

are classified as Miami Silt Loam (MnB2) and Strawn Clay Loam (SuC3). Soil borings

conducted on-site found soils to be soft to medium stiff cohesive soils. Refer to Subsurface

Investigation & Geotechnical Recommendations report prepare by Alt & Witzig Engineering,

Inc. dated October 29, 2015 for detailed soils information.

The immediate project site has a watershed are of 3.43 acres. Refer to Attachments for

delineation of watershed limits of project site area.


Stormwater Analysis

The quantity of stormwater runoff generated from a watershed can be affected by land

development and site improvements. Construction activities can alter the surface vegetation

and grades along with new hard surface areas reducing groundwater infiltration. A reduction in

infiltration will result in greater overland stormwater runoff rates. This study will analyze and

evaluate the net effect the proposed site improvements will have on the existing site.

The Rational Method was used to calculate 2-year and 10-year predevelopment conditions and

the 10-year post development conditions. The Modified Rational Method was used to calculate

the 100-year post development condition to determine the peak discharge rate.

Pre-Development Watershed – Project Limits

Tc = 20 minutes

Slope: +6%

Hydraulic Length: 700 feet

Land coverage: lawn, grasses, light woods

Refer to Attachments for Existing Watershed Map.

Post Development Watershed – Project Limits

The proposed development divides the existing watershed into two separate drainage areas

which each area will be served by a detention area. Refer to Attachments for Post

Development Watershed Map.

Detention Basin Drainage Area

Area: 1.33 acres

Development: new building, walks, patio and open lawn

South Detention Basin Drainage Area

Area: 2.10 acres

Development: parking, drive, walks and open lawn

2-Year Pre-Development Runoff = 2.761 cfs

Calculation for the 2-year storm based on Project Watershed Limits with a 20 minute rainfall

duration. Refer to Attachments for calculation worksheet.

10-Year Pre-Development Runoff = 4.514 cfs



10-Year Post-Development Runoff = 8.211 cfs




100-Year Post-Development Runoff = 5.998 cfs peak discharge

Calculation for the 100-year storm based on Project Watershed Limits. The Modified Rational

Method was used to develop the peak discharge rate with a 2-year Pre-Development allowable

release. Total required storage, for 100-year storm, = 10,886 cu. ft. Refer to Attachments for

calculation worksheet.

Detention Basin Design

Sub-watershed drainage areas for the proposed development were defined. The North

Detention Basin receives approximately 25% of impervious surface runoff and the South

Detention Basin receives approximately 75% of impervious surface runoff. Refer to

Attachments for post-development watershed map and calculation worksheet.

Peak Discharge Storage = 10,886 cu. ft. (minimum storage required)

Detention basins storage capacity = 11,024 cu. ft.

Detention basins freeboard capacity = 7,995 cu. ft.

Detention basin total capacity = 20,019 cu. ft.

North Detention Basin at 25% = 2,939 cu. ft. (minimum storage required)

North Detention Basin Capacity = 3,302 cu. ft.

Available Freeboard = 2,247 cu. ft.

Total Storage Capacity = 5,549 cu. ft.

South Detention Basin at 75% = 7,947 cu. ft. (minimum storage required)

South Detention Basin Capacity = 8,722 cu. ft.

Available Freeboard = 5,748 cu. ft.

Total Storage Capacity = 14,470 cu. ft.

Outlet Pipe Design

Outlet pipes are designed to reduce water levels in the detention basins at the 2-year pre-

development runoff rate. The North Detention Basin will drain into the South Detention Basin

and the outlet pipe from the South Detention Basin will drain into the existing swale along

Wernle Road. Calculations performed to determine the orifice size of the outlet pipe. Refer to

Attachments for calculation worksheet.

2-Year Pre-Development Runoff = 2.761 cu. ft.

Calculated orifice opening = 0.31 sq. ft.

Proposed outlet pipe = 0.36 sq. ft. (8” HDPE corrugated, smooth

interior)

(Note: an orifice plate may be placed inside the Control Structures to reduce opening to

0.31 sq. ft. if deemed necessary)


Outlet pipe for overflow conditions was designed on the South Detention Basin to allow for

emergency release of storm runoff greater than the 100-year storm peak discharge storage.

Outlet pipe was designed to meet or be less than the 10-year post development storm runoff.

Refer to Attachments for worksheet.

10-Year Post Development Storm Runoff = 8.211 cfs

Based on “Chart for Flow for Circular Pipes Flowing Full" (Manning Equation n = 0.013)

Pipe Design for 8.0 csf = 18” diameter, 0.5% slope at 4.2 fps velocity

Site Grading Plan Revisions

Drawing C2.0 Site Grading Plan has been revised, dated 09/22/16 showing revised Detention

Basin design and storm piping. A 6” perforated drain pipe was added to the stone drainage

bed along the downslope side of the parking lot. This perforated pipe will aid in the

conveyance of storm water directly to the detention basin and reduce overland surface flow

and possible erosion problems. Refer to Attachments for revisions.

Site Details Revisions

Drawing C5.0 Site Grading Plan has been revised, dated 09/22/16 showing a revised detail for

the parking lot stone edging and new details for the storm drainage control structures and

inlets. Refer to Attachments for revisions.


Post Construction Stormwater Management Plan

1. Description of potential pollutant sources from proposed land use that may reasonably be

expected to add a significant amount of pollutants to stormwater discharges.

Pollutant sources after construction are minimal. There will be no on-site fueling stations

or operations that are high risk. Potential pollutant sources may include fuels/oils for

snow removal, lawn and landscape maintenance equipment. Runoff from parking areas

may include pollutants from vehicles. All non-pavement areas will be lawn which sill

reduce surface runoff of stormwater and allow filtration into subsoils.

2. Location, dimensions, detailed specifications, and construction details of all post

construction stormwater quality measures.

Stormwater quality measures are shown on SWPPP Plans and Details, Drawings C3.0,

C3.1 and C3.2. Stone drainage beds and stone drainage trenches are shown on

Drawings C2.0 and C5.0.

3. Description of measures that will be installed to control pollutants in stormwater discharges

after completion of construction activities.

Post construction measures include stone drainage bed along parking lot to trap runoff

sediment and pollutants from pavement areas. The stone drainage trench in the bottom

of the detention areas will help trap sediments and pollutants that settle in the basins.

The storm inlets have a sump at the bottom of the structures to collect sediments and

trash.

4. Sequence of installation of measures.

Sequence for storm water and erosion control measures are shown on Drawing C3.1

SWPPP Details.

5. Measures to prevent or minimize adverse impacts to stream and riparian habitat.

Stone rip-rap stone will be placed at ends of outlet pipes to reduce adverse effects of

storm water discharge into the existing drainage swale along Wernle Road.


6. Description of maintenance guidelines for measures including: Facilitates proper long-term

function; and availability to future parties whom will be responsible for operation and

maintenance of measures.

Post development and long term maintenance functions to be performed by Owner

include:

Periodic inspections of stone drainage beds, stone drainage trenches and stone

rip-rap outlet pads to restore disturbed stones and remove any build up of

sediment and trash. Function to be performed minimum twice per year and after

major rain event.

Periodic inspections of storm structures (inlets and control structure basins) to

remove any build up of sediment and trash. Function to be performed minimum

twice per year.

Repair and restore any lawn erosion on a as needed basis.

Sweep parking lot pavements on a regular basis to remove sediment and debris.

Function to be performed twice a year minimally - once in the fall before winter

weather and again in the spring after the winter weather. Other sweepings shall

be done as needed.

Post development and long term maintenance functions to be included in Owner's

Standard Operations Manual to establish both short and long term care.

Rainfall Frequency Atlas of the MidwestRichmond, IN ‐ Area 6

Time

(Hr) (Inches) (In/Hr) (Inches) (In/Hr) (Inches) (In/Hr)

0.083 0.330 3.976 0.470 5.663 0.730 8.795

0.167 0.580 3.473 0.820 4.910 1.270 7.605

0.250 0.750 3.000 1.050 4.200 1.630 6.520

0.500 1.020 2.040 1.440 2.880 2.240 4.480

1.00 1.300 1.300 1.830 1.830 2.840 2.840

2.00 1.600 0.800 2.260 1.130 3.510 1.755

3.00 1.770 0.590 2.490 0.830 3.870 1.290

6.00 2.070 0.345 2.920 0.487 4.540 0.757

12.00 2.400 0.200 3.380 0.282 5.260 0.292

18.00 2.590 0.144 3.660 0.203 5.690 0.316

24.00 2.760 0.115 3.890 0.162 6.050 0.252

2 Year 10 Year 100 Year

Wernle Administation Building

2‐Year Pre‐Development ConditionsWatershed Area "A" 3.43 acres

Runoff Coefficient "C"

Existing cover: Grass / Trees

Existing grade: +6%

SCS Hydrologic Soils "C" at 2‐6% slopes: 0.16 to 0.21

SCS Hydrologic Soils "D" at 2‐6% slopes: 0.20 to 0.25

Projected Runoff Coefficient = .035

(assumed based on strong slopes, clay soils)

Rainfall Intensity "I":

2 Year, 20 minute storm = 2.3 in/hr

Q = ACI

Q = (3.43) (0.35) (2.3)

Q = 3.027

2‐Year Pre‐Development Runoff = 2.761 CFS


10‐Year Pre‐Development ConditionsWatershed Area "A" 3.43 acres

Runoff Coefficient "C"

Existing cover: Grass / Trees

Existing grade: +6%

SCS Hydrologic Soils "C" at 2‐6% slopes: 0.16 to 0.21

SCS Hydrologic Soils "D" at 2‐6% slopes: 0.20 to 0.25

Projected Runoff Coefficient = .035

(assumed based on strong slopes, clay soils)



Q = ACI

Q = (3.43) (0.35) (3.76)

Q = 4.514

10‐Year Pre‐Development Runoff = 4.514 CFS

10‐Year Post Development ConditionsTotal Project Watershed Drainage Area = 3.43 acres

Total Non‐impervious areas = 2.655 acres

Total Impervious areas = 33,695 sq.ft. = 0.775 acres

Building 6,600 sq.ft.

Parking 21,500 sq.ft.

Walks 5,595 sq.ft.

Weighted C = (3.43) (0.35) + (0.775 )(0.98) = 0.57

3.43



Q = ACI

Q = (3.43) (0.57) (4.20)

Q = 8.211

10‐Year Post‐Development Runoff = 8.211. CFS


100‐Year Post Development ConditionsTotal Project Watershed Drainage Area = 3.43 acres

Total Non‐impervious areas = 2.655 acres

Total Impervious areas = 33,695 sq.ft. = 0.775 acres

Building 6,600 sq.ft.

Parking 21,500 sq.ft.

Walks 5,595 sq.ft.

Weighted C = (3.43) (0.35) + (0.775 )(0.98) = 0.57

3.43

Modified Rational Method

Storm Duration

"D"

Rainfall

Intensity

"I"

Inflow

Rate

"Q"

(Q=ACI)

Allowable

Release

2‐Year

Pre‐Dev

"QAR"

Storage

Rate

(Q ‐ QAR)

(hrs) (in/hr) (cf/sec) (cf/sec) (cf/sec) (cf/sec) (cf)

0.083 (5 min) 8.795 17.195 2.761 14.434 0.100 4,349

0.167 (10 min) 7.605 14.868 2.761 12.107 0.168 7,339

0.25 (15 min) 6.520 12.747 2.761 9.986 0.208 9,063

0.5 (30 min) 4.480 8.759 2.761 5.998 0.250 10,886 Peak

1 2.840 5.552 2.761 2.791 0.233 10,133

2 1.755 3.431 2.761 0.670 0.112 4,866

3 1.290 2.522 2.761 ‐0.239 ‐0.060 ‐2,602

6 0.757 1.479 2.761 ‐1.282 ‐0.641 ‐27,914

12 0.438 0.857 2.761 ‐1.904 ‐1.904 ‐82,939

18 0.316 0.618 2.761 ‐2.143 ‐3.214 ‐140,022

24 0.252 0.493 2.761 ‐2.268 ‐4.536 ‐197,601

North Retention Basin Area = 27% Impervious Areas

27% of Peak Discharge = 2,939 cf

South Retention Basin Area = 73% Impervious Areas

73% of Peak Discharge = 7,947 cf

Required Storage

(QAR*D/12)


Detention Basin Capacity

North Detention Basin Area VolumeContour Elevation 26 3,859 sq.ft. Elevation 26

2,831 cu.ft. = Top of StorageContour Elevation 25 1,803 sq.ft.

471 cu.ft.Contour Elevation 24.50 80 sq.ft.

Storage Capacity 3,302 cu.ft.

Detention Freeboard Area VolumeContour Elevation 26.5 5,128 sq.ft. 0.5 Freeboard

2,247 cu.ft.Contour Elevation 26 3,859 sq.ft.

Freeboard Capacity 2,247 cu.ft.

TOTAL CAPACITY 5,549 cu.ft.

South Detention Basin Area VolumeContour Elevation 23.5 5,002 sq.ft. Elevation 23.5

4,604 cu.ft. = Top of StorageContour Elevation 23 4,206 sq.ft.

3,433 cu.ft.Contour Elevation 22 2,660 sq.ft.

685 cu.ft.Contour Elevation 21.5 80 sq.ft.

Storage Capacity 8,722 cu.ft.

Detention Freeboard Area VolumeContour Elevation 24.5 6,494 sq.ft. 1' Freeboard

5,748 cu.ft.Contour Elevation 23.5 5,002 sq.ft.

Freeboard Capacity 5,748 cu.ft.

TOTAL CAPACITY 14,470 cu.ft.

Summary Provided RequiredNorth Detention Basin Storage 3,302 cu.ft. 2,939 cu.ft.South Detention Basin Storage 8,722 cu.ft. 7,947 cu.ft.

Total 12,024 cu.ft. 10,886 cu.ft.

North Detention Basin freeboard 2,247 cu.ft.South Detention Basin Freeboard 5,748 cu.ft.

Total 7,995 cu.ft.

TOTAL BASIN STORAGE CAPACITY 20,019 cu.ft.


Outlet Pipe Design Calculations

Orifice/Culvert Flow Equation Q=CA(2gH)1/2

To find Orifice/Opening Area A = Q

C(2gH)1/2

2‐Year Pre‐Development Runoff = 2.761 cfs

A = 2.761

(0.60) (2) (32.2) (3.43)1/2

A = 2.761 = 0.31 sf

8.917

Outlet Pipe Design: 8" HDPE Corrugated Pipe = 0.363 sf

Detention Basin Outflow Pipe Design

Outflow pipe flow based on 10‐Year Post Construction Rainfall

= 8.211 cfs

Per 'Chart for FLow foR Circular Pipes Flowing Full" (Manning Equation n = 0.13)

8.211 cfs at 0.5% slope = 18" Pipe with 4.2 fps velocity

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