Key Risks for NSR Drinking Water Supplies
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Source Water Protection- Quality and Quantity EPCOR’s Watershed Protection Program for the Edmonton Drinking Water System Steph Neufeld, M.Sc. Watershed Specialist Quality Assurance EPCOR Water Services Oct 4, 2016 1 Watershed Protection Plan Goals To ensure clean and adequate water supplies for all water treatment plants that EPCOR operates through a watershed approach To ensure minimal effects of operations on water quality and aquatic ecosystem health to receiving water bodies 2 Capital Region WWTP Gold Bar WWTP Rossdale WTP E.L. Smith WTP 3 EPCOR’s Approach Watershed Management Implementation Working in partnership to set objectives and Supporting programs and organizations that targets for the watershed, water quality, and implement programs to reduce contaminants quantity and develop water policies that entering source waters and ensure healthy influence management. aquatic environments and watersheds. Research and Monitoring Education and Awareness • gathering scientific data on water quality Educating and informing industry, and quantity stakeholders, and the public of the importance • fostering collaborative long-term monitoring of watershed protection and best programs management practices through strategic • evaluating source waters and effluent partnerships impacts • participating in research partnerships. 4 EPCOR’s Approach Watershed Management Implementation Planning on the LAND to manage water quality Restoring watershed function and integrity. and quantity. Physical change on the landscape. Research and Monitoring Education and Awareness • Is water quality changing? Ensuring everyone is in the ‘loop’. • Is there enough water, now and in the future? 5 Research and Monitoring ■ Land use and cover mapping ■ Upstream water quality monitoring program ■ Water quality characterization ■ Water quantity: climate change effects and natural variability ■ Water use: now and in the future 6 What affects water quality and quantity in a waterbody? •Natural processes •Climate- water quantity •Landscape characteristics (topography, land use/cover, wildlife) •Underlying geology •Anthropogenic inputs and alteration • Point source pollution (industrial and municipal effluent) • Non-point source pollution (land use)- increase in quantity and timing What happens in the watershed reflects the water quality in the receiving waterbody. 7 Recent Water Supply in the NSR 568 554 Post Dam ■ Two dams regulating Pre Dam flow in watershed 416 • Brazeau built in 1961 364 354 • Bighorn built in 1972. 298 ■ Bighorn dam reservoir 251 261 228 225 1,418,208 dam3. 183 152 • Abraham Lake 142 Average Average Monthly Flow (cms) 132 134 130 112 114 118 ■ Brazeau reservoir 69 3 485,382 dam . 36 33 39 42 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Crescent Falls - Bighorn Canyon 8 WhenWater the supply water- quantity comes -insnow the NSR melt! 500 450 Summer storms Glacial melt: 3% 400 350 Allocations: 26% Consumptive use: 3% /s) 300 Spring runoff 3 250 Flow (m 200 150 100 50 0 Jul Apr Jan Jun Oct Mar Feb Aug Nov May Sep Dec Month 9 Percent of River Withdrawn For WTPs 10 Average= 2.7% MLD daily= 366 9 8 7 6 5 4 3 2 Percent of daily river flow withdrawn by EPCORs WTPs EPCORs by withdrawn flow river daily of Percent 1 0 Jan-00 Jan-01 Jan-02 Jan-03 Jan-04 Jan-05 Jan-06 Jan-07 Jan-08 Jan-09 Jan-10 Jan-11 Jan-12 Jan-13 Jan-14 10 Recent Drought Scenarios: 2002 ■ Water plant production reached peaks that are similar to current 2015 demand (with higher population). ■ Water plants were able to meet 2002 demand with historical low flows and changing water quality. It is appears that dams on the river were able to sustain higher flows in the river during the drought. Daily Minimum River Flow at Edmonton (m3/s) 1911-2013 11 Historical Water Supply in the NSR Red Line: Recent average flow of 7,160,000 dam3 12,000,000 10,000,000 8,000,000 6,000,000 Mean Annual Discharge (dam3) 4,000,000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 Crescent Falls - Bighorn Canyon 12 Work by Dave Sauchyn How low can it go? 10000 Maximum Average Minimum 1000 100 Average Average weekly flow (m3/s) 10 1 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 Year Very low- 10 m3/s where the river is likely series of disconnected pools 13 A long drought…. 450 1714 - 1718 Estimated Flow 400 Adjusted 1714 - 1718 flow 350 300 /s) 3 250 200 Flow (m 150 100 50 0 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 Week 14 Percent of Flows Withdrawn10 for12 Water14 Treatment16 18 20 0 2 4 6 8 How much water would Edmonton use? HowEdmonton much water would 1 3 5 7 9 Based on average weekly averageBased weekly on use (2000 11 13 15 17 19 21 23 15 Week 25 27 29 31 33 - 35 2015) 37 39 41 43 Flow Regulated Nauralized flow 45 47 49 51 Percent of Flows Withdrawn for Water Treatment 10 20 30 40 50 60 70 0 1 weeks every weekofWorst 1000 years 3 5 7 9 11 13 15 17 19 21 23 1,591,717average 22% dam3 of orflow 16 Week 25 27 29 31 33 35 37 39 41 43 45 47 49 51 Climate Change and Low Flow ■ Number of extended periods of low flow prior to year 1900. ■ Most challenging climate change scenario found to be hydrological drought superimposed on lower mean summer flows. ■ Big Horn and Brazeau dams mitigate some drought impacts. ■ Worst-case scenario: mega-drought cycles as seen in tree-ring reconstructions of natural flows is manageable due to the dams ■ There are other users in the system and dam management may be an important factor in low water conditions 17 Water QualityLinked is to Hydrology Water Colour (TCU) 100 120 20 40 60 80 0 Jan 1 Jan 15 Jan 29 Feb 12 Feb 26 Mar 11 Mar 25 Apr 8 Apr 22 May 6 May 20 Jun 3 Jun 17 18 Jul 1 Jul 15 Jul 29 Aug 12 Aug 26 Sep 9 Sep 23 Oct 7 Oct 21 Nov 4 Nov 18 Average Average 2008 2007 2005 1999 1998 Dec 2 Dec 16 Dec 30 Land Use Drives Quality and Quantity Land Cover Based on Satellite Imagery 19 Research and Monitoring: Land Use Manure Production from Livestock 20 Research and Monitoring: Water Quantity Research and Monitoring: Examples7.2 million m3/yr Trend↓ -1.4%/decade over 97 years ~2% of annual flow from glaciers 50% of annual flow to Sask - PPWB (1969) Water supply to the Capital Region: ~90% comes from 4 upper sub-basins 21 Example: Edmonton’s Drinking Water System Risk / Risk Analysis Chart. Source Land-Uses / Potential Contaminant Source/Activity Inherent Risk Residual Risk Small urban waste discharges from WWTP H L POINT Municipal sewage lagoon discharges H L Pipeline break M-H M-L Industrial discharges H L Livestock waste excretion H L Livestock physical alteration of watershed M-H L Agricultural cropping activities M-H L Agricultural land cover and use M-H L Wildlife activity in watershed. M-H L Rural septic fields M-H L Small urban storm water runoff M-H L Forest harvesting activities M-H L Pine beetle infestation M-H L Forest fires M-H L Waste disposal sites M-L L Alteration in climate (natural and anthropogenic) M-H L City of Edmonton storm water runoff NON-POINT H L Contamination of pet fecal matter in urban areas M-H L Proximity to transportation corridor M-H L Spill on a bridge M-H M-L Recreational activities M-L L Ground water contamination from airport M-L L Gravel extraction activities M-L L Coal surface mining L L Disposal of animal remains within watershed M-L L Dam operation and management M-L L Industrial contamination of shallow aquifers M-H M-L Industrial land spillage M-H M-L Intentional contamination at critical source intakes M-H M-L Insufficient raw water quantity M-L L OTHER Catastrophic failure of dams 22 M-H L Contamination of raw water due to intentional dumping or release of chemicals from industries M-H M-L Watershed Management in Alberta Water for Life Cumulative Regulations and -safe, secure drinking water Effects Standards -healthy aquatic ecosystems -reliable, quality water supplies for a Management sustainable economy Source Water Protection Alberta Water Council Land Use Framework Plans •Water policy advice •Enabled by Alberta Land •Focus on drinking water Stewardship Act Watershed Planning and Regional Plans Drinking Water Safety Advisory Councils •Legislatively binding Plans •Water quality and watershed outcomes Sub-basin plans Water Quality Approvals and •Lake management plans Management Frameworks Environmental •Sub-watershed plans •Water quality outcomes Performance Plans 23 Integrated Source Water Protection • NSWA • AEP • Ag Canada • Industry • Way We Green • ENGOs • Integrated Watershed Management Plan • Source Water Protection Plan • NSWA • IH Water • Alberta Environment Management Plan • Agriculture Canada • Regional Plan • Industry • ENGOs 24 Key Risks for NSR Drinking Water Supplies . Acute episodic events . NSR contamination from upstream spills . River basin flood (e.g. 1915 scenario) . Upstream water quality long-term degradation from non-point sources (storm) . Climatic variability trends to the extreme . Less precipitation leads to lower water balance . NSR water quality degradation during seasonal low flows Source: 2016-2018 Watershed Protection Program Plan 25 Strategic Programs for Managing Risks . EPCOR’s SWPP for NSRB . NSR Total Loadings Plan (TLP) for TSS . GBWWTP + City Storm/CSO + ACRWC . EPCOR’s Drinking Water Safety Plan . Source Water Risks (and key action items) . Stewardship Commitments under EnviroVista Approval for E-Waterworks . Water supply climate change studies for historic NSR mean annual and weekly flows (Sauchyn et al.) 26 New Initiatives for Risk Mitigation .