Presentation is loading. Please wait.

Presentation is loading. Please wait.

Western Water Workshop Front Range Groundwater: Scarcity and Opportunity July 21, 2010.

Similar presentations


Presentation on theme: "Western Water Workshop Front Range Groundwater: Scarcity and Opportunity July 21, 2010."— Presentation transcript:

1 Western Water Workshop Front Range Groundwater: Scarcity and Opportunity July 21, 2010

2 Topics for Presentation  What problem?  The inevitability of groundwater dependence  Conservation as an answer  A portfolio approach  Infrastructure  Where to next?  Storage for future use  The public policy dilemma

3

4 Why Groundwater?

5 Woodmoor’s Raw Water System Development Historical Perspective Why non-tributary groundwater? –No accessible surface water provider –Readily available –Valuable resource –Develop incrementally –Relatively low cost for initial development –Protected from contamination –Drought resistant Groundwater is not “running out” but will cost more as groundwater levels continue to decline More wells, more energy needed to pump at deeper levels, reduction in well yield, and higher maintenance costs

6 Dawson: 50 – 150 gpm 700 ft total depth Denver: 50 – 250 gpm 1300 ft TD Denver Basin Aquifers Interbedded Sandstone, Shale and Clay Aquifers Arapahoe: 200 – 500 gpm 1900 ft TD Laramie-Fox Hills: 75 – 150 gpm (projection) 2500 ft TD Source: USGS HA-730-C

7 All Rights Reserved © West Water ResearchConfidential and Proprietary Information Groundwater dependent communities on the Front Range

8 What Problem?  100 year theoretical life of the aquifer  The practical life is 30 to 40 years Source: Colorado Foundation for Water Education

9 NEIGHBORHOOD DRAWDOWN DWSD 8

10 Some simple math  A single family home needs about one-half acre-foot of delivery  The aquifer (all 4 layers) holds about 1.5 acre-feet of water per acre  Land density is about 3.5 units per acre.  At build-out, the water needed is 1.65 acre- feet per acre USING ALL 4 AQUIFERS!

11 Demand vs. Supply Service Area Build-out

12 EFFECTS OF GROWTH DWSD 9

13 DWSD 10 FULL GROWTH

14 KEY FINDINGS  Total Gross Gap: 28,600 – 28,752 AF  Counties with largest gap:  El Paso (unincorporated): 22,600 AF Increased demand: 9,250 AF Loss of existing groundwater supplies: 13,350 AF  Lake: 1,950 AF Increased demand- Unincorporated areas Arkansas Basin Consumptive Use Water Needs Assessment Arkansas Basin Roundtable

15 Conservation  Seasonal variation and daily peak  A water manager has to meet both  Peaking on a deep aquifer well stresses the aquifer further reducing well yield

16 Residential Water Use

17 2005 Annual Hydrograph

18 Managed Peak Day Demand

19 Conservation/Demand Management Programs Passive Conservation Information/Education –Bill Stuffers –Articles –Water-Wise Garden Open House –New “Product” Exhibit –“Green Builders” BMPs –Water Use Audit Programs Demand Reduction –Annual Demands 5 % - 10% –Max Day Demands 5 % – 10%

20 Conservation/Demand Management Programs Active Demand Management –Reduction of Unaccounted for Water –Rebates –Designated Watering Days (max-day) –Designated Watering Hours (annual demand) –Budget Billing –Conservation Rates –“Water Conservation” Building Codes Demand Reduction –Annual Demand 10% - 15% –Max Day Demand 15% - 25%

21 Conservation/Demand Management Programs Restrictions –Turf Limitations – size – type –Punitive price/rates structures –Landscape Designs Review and Approval –Irrigation System Review and Approval –Limit Designated Watering Days (max-day) –Limit Designated Watering Hours (annual demand) –Budget Billing – reduce budgets – increase rates Demand Reduction –Annual Demands 15% - 35% –Max Day Demands 25% - 40%

22 2007 Summer Water Use Program (June 1st. through September 1st.) Common Elements Outdoor Use Calendar –Odd # address Sunday, Wednesday, Friday –Even # address Saturday, Tuesday, Thursday –NO watering on Monday Prohibited Watering Hours –No Watering 10 am to 6 pm Water Waste –It is a violation to waste water by causing runoff of water on streets or into drainage facilities

23 2007 Summer Water Use Program (June 1st. through September 1st.) Outdoor Watering & Irrigation Turf Grass –3 times per week per calendar New Seed & Sod –Lawn permits from District - additional irrigation times allowed - 2 week permit for sod - 4 week permit for seed Flowers, Vegetables, Trees and Shrubs –Hand-held hose or low-volume non-spray irrigation, any day, any time. Designated Community Parks, open space and Athletic & playing fields –Water Budget developed with the District

24 A Portfolio Approach  Conservation is fundamental  Do you issue a new tap on conserved water?  Demand Harding  The Yuck Factor  Indirect Potable Reuse  The Space Shuttle model  Groundwater remains in the portfolio

25 Exchange Conserve. Surface Water Integrated Supply Strategy Ground- water Exchange Conser- vation DEMANDDEMAND DEMANDDEMAND CurrentFuture Ground- water Exchange Ground- water Surface Water CurrentFuture

26 Infrastructure  Delivery infrastructure is expensive  The remaining sources are not where the customers are located  Is this speculation?

27 All Rights Reserved © West Water ResearchConfidential and Proprietary Information Infrastructure Development: Well Field  The wells will be grouped into pods and developed in phases to minimize up front capital costs.  The development of the well field includes down hole drilling, power hook up and collection piping.  The well field will include between 20 and 35 wells drilled at depths of 1,500 to 2,800 feet.  There is a substation on the southeast side of the ranch reducing the costs of power hook up.  A collection network of 8” – 20” pipe will be constructed over a phased period as market demand comes on line.  Pump station and electrical transmission infrastructure development costs are included in the well field development costs.  Estimated net present value of the well field development costs range from $29 million to $41 million based upon sales scenario. Acquire Water Right Infrastructure Development Sell Water Wholesale

28 All Rights Reserved © West Water ResearchConfidential and Proprietary Information Infrastructure Development: Conveyance (cont.)  Brown and Caldwell has prepared initial pipeline route and cost estimates.  The routes and pipe size were selected based upon the four most likely demand scenarios.  The pipeline route heading south consists of 9 miles of 16” to 24” inch diameter pipe.  The pipeline routes heading north consist of 12 to 26 miles of 16” to 24” inch diameter pipe.  Pressure reducing facilities and pump station costs are included in conveyance cost estimates.  Estimated net present value of the conveyance costs range from $23 million to $45 million based upon sales scenario. Acquire Water Right Infrastructure Development Sell Water Wholesale

29 Groundwater Dependence  The Denver Basin Aquifers  Rate of depletion  Future sources of supply? The Denver BasinUSGS Study: 2008

30 Groundwater Dependence  Designated Basins  A Modified Prior Appropriation Doctrine (Groundwater Act of 1965)  Management Districts Source: Division of Water Resources

31 2007:A Two Pronged Approach  Base study of the Upper Black Squirrel Designated Groundwater Basin  Colorado Geologic Survey, Dec, 2008  A Public Policy Forum sponsored by the Arkansas Basin Roundtable (Sept, 2007)  Peer Review by the Director of Natural Resources, Dec, 2008

32 Alluvial aquifer east of Colorado Springs

33 Lying atop a bedrock layer of Pierre shale

34 Depletion began in the 1960’s

35 1964 to 2004 well depletions

36

37 DescriptionTotal Area (acres)Total Storage Capacity (ac-ft) Total Saturated Primary Alluvium78,850474,643 Total Unsaturated Primary Alluvium78,850605,865 - Unsaturated Alluvium (50ft-water table)38,000218,327 - Unsaturated Alluvium (75ft-water table)20,25088,164 - Unsaturated Alluvium (100ft-water table)8,54025,996 Upper Black Squirrel Creek Basin Alluvium Storage Calculations * Using a storage coefficient of 0.18 Designated Groundwater

38 Conference in Sept, 2007 http://ibcc.state. co.us/News/

39 Conflicting Conclusions  The legal system is working just fine  One at a time legal cases are very expensive

40 Recharge for Future Use  Recharge as augmentation is not recharge for future storage  Rules in the Denver Basin by SEO

41 A National Issue  National Academy of Sciences MUS study  EPA Experts Meeting May 5-6, 2009

42 Where do we go from here?  How do quantity and quality work together?  How will the State permit projects?  A pilot by the General Assembly?

43 Where do we go from here? Source: DNR Director Harris Sherman, Dec, 2008

44 Opportunity?  Can we collaborate before we reach a crisis?  Can the Prior Appropriation Doctrine accommodate the future of Colorado’s water resources?  The River of 1890  Groundwater is tributary until you prove a negative, i.e. non-injury  Is the legislature the appropriate venue to change groundwater policy?

45


Download ppt "Western Water Workshop Front Range Groundwater: Scarcity and Opportunity July 21, 2010."

Similar presentations


Ads by Google