Nonpotable Strategy Project RPMT Briefing
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Transcript Nonpotable Strategy Project RPMT Briefing
Colorado Springs’ ASR
Program
Presented by Cortney Brand
Western Water Workshop, Gunnison, CO
July 28, 2005
Outline
Colorado Springs’ Water
System
Long-Term Water Supply Plan
Denver Basin Aquifers
Benefits of ASR
ASR Operational Concept
Feasibility Investigation
Long-Term Testing
Next Steps
Rampart Reservoir
Colorado Springs’ Water System
Serve water to approx. 410,000 people
97% surface water (primarily snowmelt)
3% alluvial and bedrock groundwater
Extensive network of diversions, tunnels, reservoirs,
pipelines and canals
Can deliver 110,000 AF/yr from 200 miles away
Current demands of 80-90 KAF/yr, projected to be 180
KAF/yr by 2040
includes existing and planned DSM programs
Supply Systems
3
1.
2.
3.
4.
5.
6.
2
4
1
Colorado Springs
FVA Pipeline
5
Local (1800’s – present)
Blue R./S. Platte (50’s)
Homestake (60’s)
Fry-Ark (60’s)
Twin Lakes (70’s)
Colorado Canal Exchange (80’s)
6
Long-Term Water Supply Plan
New major delivery system – Southern
Delivery System (SDS)
43-mile, 66-inch pipeline from Arkansas River
Delivery capacity of 78 MGD
Online by around 2011-12
Bridge gap by:
Local water system improvements
Nonpotable water development & distribution
Groundwater development & ASR
Denver Basin Aquifers
Extensive sedimentary bedrock
aquifer system
Non-renewable
Underlies ~7,000 mi2 area (40% of
Denver
Basin
Colorado Springs)
Relatively low transmissivities and
well yields
Colorado Springs has 15 Denver
Basin wells
Delivery capacity of 3,600 AF/yr
Used for supplemental potable
supply and irrigation (parks, etc.)
Colorado
Springs
Why Pursue ASR?
Unique (for Front Range) combination of surface and
groundwater supplies and infrastructure
Additional water storage capacity
Leverage investment in groundwater supply infrastructure
Use off-peak capacity in treatment plants and pipelines
Bank water for future dry years
Improve sustainability of Denver Basin groundwater
Diversify water supply portfolio (risk mitigation)
ASR Operational Concept
October – April (Inject/Store)
Proactively Deliver from Reservoir Storage
(make space to capture spills)
Treat
Pipe to wells
Inject into aquifers
ASR Operational Concept
May – September (recover)
Disinfect
Recover Water
Deliver to Tanks
ASR Feasibility Investigation
Conducted Fall of ’04
Injection/recovery testing at two wells
Water sampling & analysis
Geochemical modeling
ASR water availability analysis
Used supply system Operations & Yield model to
quantify “spills”
Conceptual plan for implementing ASR
ASR Testing Results
Arapahoe Well
Injection rate of 500 gpm
(pumping rate of 600+ gpm)
No water quality concerns
Denver Well
Injection rate of 75 gpm
(pumping rate of 75+ gpm)
Potential recovered water
quality concerns
Need pH adjustment
Northgate Tank Site
ASR Water Availability
80%
Percent of Time Available
70%
Short-term goal (5 yrs)
60%
Ultimate goal (10 yrs)
50%
2005
2010
2015
40%
2020
2030
30%
2040
20%
10%
0%
1,000
2,000
3,000
4,000
5,000
10,000 15,000 20,000 25,000 30,000 35,000
Amount Available (ac-ft)
Long-Term Testing
Started in July – complete in December
Objectives
Determine sustainable, long-term injection rates
Verify water quality
Determine backwash frequencies
Arapahoe Well
• 500 gpm
• 3 months injection
• 2+ months recovery
Denver Well
• 50-75 gpm
• pH adjustment
• 2 injection/recovery cycles
Next Steps
“Crawl, Walk, Run”
1. Evaluate long-term testing results
2. Operate Northgate ASR facility in 2006
Will recovered water need to be re-treated?
Can we maintain injection rates?
Is the system easy to operate?
Develop and implement water accounting practices
3. Retrofit additional wells
4. Work toward goal of 2-3 KAF/yr capacity by 2010
Questions?