Phase 3 interim report August 2014 1. Local non-profit source water protection agency Implementing...

Post on 16-Dec-2015

214 views 1 download

Tags:

transcript

1

WUQWATR Wascana Riparian Health

Assessment ProjectPhase 3 interim report August 2014

2

Local non-profit source water protection agency

Implementing “Getting to the Source”, with 82 recommendations

Covers two watershed area, the Wascana and the Upper Qu’Appelle

Agriculture programming, invasive weed management and research

More info at www.wuqwatr.ca

Who is WUQWATR?

3

WUQWATR Watersheds

4

Lack of Riparian Health Assessment data in Wascana Watershed identified in 2008

Funding received for project design from Saskatchewan Watershed Authority in 2009/10

Field work was delayed by flood conditions in 2011

Wascana Riparian Health Assessment

5

First field assessments in summer 2012 within City of Regina boundaries

Further design and field assessments took place in 2013 on Creek upstream of Regina

Third phase completed this summer downstream of Regina to the Qu’Appelle, and on portion of Cottonwood Creek

Wascana Riparian Health Assessment

6

Phase 3 study area

7

Smallest Saskatchewan watershed area, with highest population density

Highly modified environment. Major urban impact, and intensive cropping Saskatchewan State of the Watershed

Report condition ranking is “Impacted” Saskatchewan State of the Watershed

Report stressor ranks “High Intensity” Issues of flooding, invasives, nutrient

loading, high streamflow downstream of Regina.

Why Wascana Creek?

8

Why Wascana Creek?

9

What is the riparian area?

10

Riparian Health Assessment uses observational data to measure indicators of riparian health

Some indicators involve identification of plant species composition and plant cover, and condition of plant life

Other indicators classify the physical condition of the bank such as structural composition and integrity

Why Riparian Health Assessment ?

11

Allows for a better understanding of the condition of key ecological functions on the landscape

Data collected can be used as a baseline to monitor condition over time

Results can compare different management zones along a waterway

Results can inform management decisions made by landowners and managers

Can be used to identify project sites

Why Riparian Health Assessment ?

12

Trap sediment Build and maintain streambanks Store flood water and energy Recharge of aquifers Filter and buffer water Reduce and dissipate stream energy Maintain biodiversity Create primary productivity

Key Ecological Functions of Riparian Areas

13

Balances erosion with bank restoration – reduces effects of erosion by adding bank elsewhere

Increases stability and resilience Maintains or restores the profile of the

channel – and extends the width of riparian area through higher water table

Measures of Riparian Function-Streambank Protection and Development

14

Utilizes two categories – Lotic for rivers and streams, lentic for lakes, sloughs, wetlands

Utilizes set questions – 12 for lotic system, 9 for lentic system

Utilizes visual observation and assigns point scores based on data

Overall Health score of 80% or greater rates “healthy”

Overall Health score of 60%-79% rates “healthy with problems”

Overall Health score of less than 60% rates “unhealthy”

Riparian Health Assessment -Method

15

Scores 80 or higher

All riparian functions are being performed

High level of riparian condition

Demonstrates resiliency and stability

Health Assessment Ratings – “Healthy”

16

Healthy Riparian Score

17

Scores range from 60-79

Many riparian functions are being performed, but some clear signs of stress are apparent

The reach area many not be as capable of rebounding from floods and human activity

Health Assessment Ratings- Healthy with Problems

18

“Healthy with Problems”

19

Scores 0 -59

Most riparian functions are severely impaired or have been lost

Reach has lost most of its resiliency, stability is compromised

Health Assessment Ratings- “Unhealthy”

20

“Unhealthy score”

21

Preferred species have deep binding root mass

Most preferred species are native plants Good balance of trees –Willow, Manitoba

Maple, Elm, Green Ash, Hawthorn Shrubs Chokecherry, Saskatoon, Dogwood Forbs and grasses - Cattails, rushes, reed

grass, native grasses

Vegetative Cover – preferred species

22

Invasive species out-compete preferred species

Often are exotic plants that lack local controls

Invasive plants impair riparian function Brome grass is pervasive throughout

watershed, replaces preferred grasses Disturbance plants grow where preferred

species have disappeared Sow thistle, burdock, dandelion

Vegetative cover – invasive and disturbance species

23

Top 4 invasive plants species

24

Top 4 invasive plant species – smooth brome

25

Top 4 invasive plant species – scentless chamomile

26

Top 4 invasive species – Absinthe

27

Health rating – Wascana Creek Downstream

85%

15%

Health Rating Composition of Wascana Creek Downstream of the City of Regina

Unhealthy

Healthy with Problems

Healthy

Figure 2: This pie chart shows the health rating composition (healthy, unhealthy, and healthy with problems) of Wascana Creek flowing from the western city limits of the City of Regina to where Wascana Creek flows into the Qu'Appelle River.

28

Average coverage score was 3 out of 6, which indicates significant areas of bare ground due to water

Lots of areas where flooding had washed out large areas, especially on outside meanders

Bare ground was more common further downstream

Results- Vegetative cover

29

Vegetative Cover

30

Average score for Wascana Creek was .04 out of 6

Prevalence of smooth brome

Also widespread scentless chamomile, thistle,

Absinth and locations with leafy spurge

Invasive species

31

Overall average score on trees and shrubs is 8.8 out of 12

Trees are present and regenerating themselves

Presence of beaver browsing lowers score

Where are the beaver dams?

Presence of preferred trees and shrubs

32

Average Wascana score of 2 out of 6

Indicates that overall only 35%-65% of the streambank is anchored with deep, binding root mass

Deep rooted vegetation

33

Average scores are 4.5 out of 6 for human caused bare ground

Average score of 4.8 for human alteration

These are good indications about local management

Human caused bare ground and alteration by human activity

34

Average Wascana score is .7 out of 6

This indicates that at least 30% of the site reach shows active lateral cutting from stream flow

Active lateral cutting

35

Lateral cutting of banks

36

Average Wascana score was 2.1 out of 9

This means that the stream cannot access its flood plain

This continues the cycle of incisement and slumping, until bank stability is achieved by erosion

Access to flood plain

37

Access to flood plain

38

Cottonwood Creek results

38%

13%

50%

Health Ratings of Cottonwood Creek

Unhealthy Healthy with Problems

Healthy

Figure 3: This pie chart shows the health rating composition (healthy, healthy with problems, and unhealthy) of Cotton -wood Creek from grid SK-730 to where it joins Wascana Creek.

39

Physical structure of streambank has been clearly compromised by high peak flows, and intense rainfall events over the year

Problems with high flows are compounded by 60 meter drop in elevation

Highly erodible glacial till soils further downstream

Clay, loam, gravel, sand

Interpretation of results – physical structure

40

Wascana Creek historical hydrograph

41

Wascana Creek hydrograph 2014 –Qu’Appelle

42

2011 hydrograph –Wascana Creek at Qu’Appelle

43

Wascana Creek water level -2014 April 1-Aug

44

Seven Bridges Road RM#189

45

WWTP - outlet

46

Scores overall lowered due to invasive plant species

Some species like smooth brome are too pervasive to be controlled

Expansion of other species like leafy spurge can be controlled

Evidence of flood damage leading to spread of invasive and disturbance plants

Interpretation of results – Invasive species

47

Flow from WWTP has altered Creek hydrograph to flow year round

Impacts from recent high flows are pronounced

Potential impacts from stormwater flows from hard surface in Regina. High peak runoff events downstream

Phase 3 Downstream of Regina

48

Constant flows are likely impacting establishment of vegetation, increasing erosive force on gravelly glacial soils

Recent major slumping at sites like Sherwood Forest and Deer Valley

Seven Bridges Road in RM #189 has serious erosion issues

Cottonwood Creek is healthy but now the receiving waterbody for the GTH stormwater system

Phase 3 downstream of Regina

49

Total results for 3 phases 150 sites

50

Healthiest sites are riparian park areas in Regina

Much engineering alteration in City and upstream, which may speed up water

Creek serves as natural pathway for invasives

Improvement will require cooperation and creativity

Overall results

51

Some agricultural impacts, such as overspray with herbicide

No notable siltation from cropping No notable impacts from livestock overall Naturalization of parks and stormwater

channels helps manage city runoff Need more information about where flows

are coming from in the watershed

Overall results

52

Questions?