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City of Edmonton’s Kennedale Wetland Mike Christensen Golder Associates WaterTech 2014
City of Edmonton’s Kennedale Wetland
Mike Christensen Golder Associates WaterTech 2014
Background: City of Edmonton’s Total Loading Plan
The City’s Total Loadings Plan (TLP) was submitted to Alberta Environment as required under the City’s Approval-to-Operate in 2009.
The goal of the TLP is to establish a framework to limit annual loadings of Total Suspended Solids (TSS) in the future to baseline levels.
TSS is a key water quality parameter of the North Saskatchewan River. TSS is also a surrogate for other pollutants. TSS is key indicator of aquatic health in waterbodies affected by urban
stormwater. TSS loading is expected to increase due to new urban land
development. City of Edmonton started implementing approaches to reduce TSS such
as the Kennedale Wetland.
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City of Edmonton’s Total Loading Plan
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Kennedale Constructed Wetland
$7.5 M end-of-pipe treatment facility. 5 ha in size. Built from a former gravel pit. Real-time automated controls to control inflows and outflows. Awarded Federation of Canadian Municipalities Sustainable Community
Award in the Water Category.
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https://www.youtube.com/watch?v=EKuqFTW1Zbs&feature=player_detailpage
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Kennedale Wetland Video
https://www.youtube.com/watch?v=EKuqFTW1Zbs&feature=player_detailpage
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Kennedale Storm Basin and Wetland
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Kennedale Wetland – Schematic Diagram
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Kennedale Wetland – Schematic Diagram
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Kennedale Drainage – Pre-Construction
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Kennedale Drainage – Pre-Construction
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Kennedale Drainage – During Construction
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Kennedale Drainage – During Construction
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Kennedale Drainage – Post-Construction
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Kennedale Drainage – Post-Construction
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Overview of the Kennedale Wetland Monitoring Program
Program extended from 2010 – 2013 Samples collected from upstream and downstream of the wetland during
both wet (stormflow) and dry (baseflow) conditions throughout the open water period
Automated samplers operational in 2011 and collected ~ 60 stormflow event samples a year
Samples analyzed for TSS, chloride, TKN, ammonia, NO3+NO2, TP, E. coli and chlorophyll a
Metals and pesticides collected periodically Sediment accumulation measured in the forebay
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Goal of the Kennedale Wetland Monitoring Program
Goal was to determine efficiency of the Kennedale Wetland
Challenge – flow measurements were not available for inflow
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Removal Efficiency =Massin − Massout
Massin x 100
Did The Kennedale Wetland Work?
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Did The Kennedale Wetland Work?
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Did The Kennedale Wetland Work?
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Results: Total Suspended Solids
Annual removal efficiency during stormflow conditions: 70 to 88%
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MH10MH1MH10Outfall
1000
100
10
1
Tota
l Sus
pend
ed S
olid
s (m
g/L)
Baseflow Stormflow
n=6 n=9 n=48 n=39
Results: Total Suspended Solids
Objective of the Kennedale Wetland was to remove 1,100 kg/d of TSS. Due to incomplete flow data, assumptions had to be made to address
this objective. The Kennedale Wetland removes ~ 1,100 kg/d of TSS during the open
water period due to the prevalence of wet conditions. Relatively little TSS removal during dry conditions, and presumably
during winter.
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Results: E. coli
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MH10MH1MH10Outfall
1000000
100000
10000
1000
100
10
1
Esc
her
ich
ia c
oli
(MP
N/1
00m
L)
n=6 n=9 n=56 n=46
Baseflow Stormflow
Annual removal efficiency during stormflow conditions: 90 to 95%
Results: Chloride
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MH10MH1MH10Outfall
500
400
300
200
100
0
Ch
lori
de
(mg
/L)
n=6 n=9 n=47 n=40
Baseflow Stormflow
Annual removal efficiency during stormflow conditions: - 90 to - 313%
Annual removal efficiency during stormflow conditions: - 30 to - 147% *
MH10MH1MH10Outfall
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
Am
mo
nia
(m
g N
/L)
n=6 n=9 n=47 n=40
Baseflow Stormflow
Results: Ammonia
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MH10MH1MH10Outfall
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.0
Nit
rite
+N
itra
te (
mg
N/L
)
n=6 n=9 n=47 n=40
Baseflow Stormflow
Annual removal efficiency during stormflow conditions: - 9 to - 62%
Results: NO3+NO2
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MH10MH1MH10Outfall
1.2
1.0
0.8
0.6
0.4
0.2
0.0
To
tal P
ho
sph
oru
s (m
g P
/L)
n=6 n=9 n=46 n=40
Baseflow Stormflow
Results: TP
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Annual removal efficiency during stormflow conditions: - 155 to 30%
MH10MH1MH10Outfall
8.0
6.0
4.0
2.0
0.0
To
tal K
jeld
ahl N
itro
gen
(m
g N
/L)
n=6 n=9 n=46 n=40
Baseflow Stormflow
Results: TKN
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Annual removal efficiency during stormflow conditions: - 26 to 32%
Summary of Removal Efficiences
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Parameter
2010 2011 2012 2013
Average Removal
Efficiency
Average Removal Efficiency
Average Removal
Efficiency
Average Removal Efficiency
Sink TSS 74 88 80 70 E. coli 82 95 90 92 Source Chloride -313 -90 -99 -115 Ammonia -30 * -55 * -147 * -74 * NO3+NO2 -23 * -14 * -9 -62 Sink/Source? TKN -26 * 32 -0.3 * 11 TP -155 30 -35 * 18
Bathymetric Survey of the Forebay
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Forebay Sediment Accumulation
1.4 m of sediment accumulation between 2010 and 2011 0.3 m of sediment accumulation between 2011 and 2013
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604
606
608
610
612
614
616
0 20 40 60 80 100 120 140 160 180
Elev
atio
n (m
)
Distance (m)
October 2010 October 2011 October 2013
Sediment Accumulation in the Forebay
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Summary
Kennedale Wetland effectively removes TSS and E. coli from stormwater.
The Kennedale Wetland met the objectives of removing 1,100 kg/d of TSS established in the City’s Total Loadings Plan.
The Kennedale Wetland has little or no effect on other parameters (i.e., chloride, nutrients).
Relatively little inter-annual variation, and Wetland still appears fully operational 4 years after construction.
The Kennedale Wetland is a successful end-of-pipe treatment facility.
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