Castle Pines North Metropolitan District Integrated Water Resources Plan Community Meeting No. 2 January 23, 2006

1. Introductions

Agenda Introductions Review Public Meeting #1 Castle Pines North’s water supply and the Integrated Water Resources Plan Groundwater Analysis Water Supply Alternatives for CPNMD Water Supply, A Statewide Perspective CPNMD Project Financing Options Integrated Water Resources Community Participation Committee Upcoming IWRP Project Activities and Community Information Meetings Questions and Comments

Content & Objectives of Each Community Meeting Meeting No. 1 – November 7, 2005 Introduced Integrated Water Resources Plan (IWRP) Presented overview of supply and demands Meeting No. 2 – January 23, 2006 Provide initial results of groundwater analysis Present preliminary alternatives Additional Meetings – Spring-Summer 2006 Discuss recommended alternatives Present Draft IWRP Finalize IWRP

Integrated Water Resources Plan Tasks Evaluate past, current, and future water demand Evaluate water conservation strategies Evaluate long-term sustainability of the District's existing groundwater supply using a groundwater model Evaluate other water supply options and find the optimum "grouping/portfolio" of options that best meets the needs of the community

2. Review Public Meeting #1

Public Meeting #1 What is the Integrated Water Resources Plan? Castle Pines North Metropolitan District's Existing Water Supply and Demands The IWRP Process Potential Supply Options

CDM’s Integrated Water Resources Planning Identify key decision makers & stakeholders Define objectives and weigh them according to stakeholder preferences Develop evaluation framework to aid in decision-making process Identify all feasible supply and demand- management options Conduct conceptual or feasibility level engineering analysis Combine options into complete alternatives to be evaluated against objectives (criteria) Use appropriate decision models and tools Evaluate alternatives in terms of supply reliability, cost, water quality, implementation, environmental impacts, and other attributes Show trade-offs between alternatives Identify risk scenarios Demonstrate how alternatives respond to risk Identify priority elements (projects) that perform well under all scenarios Develop adaptive strategy for remaining elements based on risk triggers Define Objectives and Framework Build Alternatives Evaluate Alternatives Develop Strategy

Historic and Projected CPNMD Water Demands

Current CPNMD Water Use by Customer Type

CPN Monthly Water Demands 50 100 150 200 250 300 350 400 Jan-99 Jan-00 Jan-01 Jan-02 Jan-03 Jan-04 Acre-ft Summer Demands > 6x Winter Demands

The Bottom Line on our Supply and Demand Groundwater is not "running out" but it will cost more in the future Challenge in meeting peak demands Regional issue affecting Douglas and Arapahoe Counties CPNMD is conducting an Integrated Water Resources Plan (IWRP) to prepare for the future Regional solutions and partnerships are being formed now

3. Castle Pines North’s water supply and the Integrated Water Resources Plan

Existing Water Supply and Demand Management Groundwater Conservation Recycled Water The Ridge Golf Course

Existing Supply Groundwater is currently CPNMD's only source of water supply 10 active wells 3 million gallons of storage Wells to treatment then pumped to storage CPNMD's existing groundwater supply is nonrenewable Groundwater is not "running out" but it will cost more in the future if groundwater levels continue to decline More wells, more energy needed to pump water at deeper levels, reduction in well yield, and higher maintenance costs

Castle Pines North Water System Development - Historical Perspective Why non-tributary groundwater? No large provider (Denver, Aurora) willing to serve the area Valuable resource Readily available Develop incrementally Relatively low cost for initial development Protected from contamination Drought resistant

4. Groundwater Analysis

Denver Basin Aquifers and CPNMD The Setting: Denver Basin Aquifers and CPNMD CPNMD Dawson Denver Arapahoe Laramie-Fox Hills Alluvial

The Setting: South-North Cross-section through CPNMD Dawson Denver Arapahoe L-FH Castle Pines Greeley

West-East Cross-section through CPNMD The Setting: West-East Cross-section through CPNMD Laramie-Fox Hills Arapahoe Denver Dawson Castle Pines North West East

Aquifer porosity and water storage – Ground water moves through connected pores and fractures in rock

Ground water overview – Confined and Unconfined Aquifers stays fully saturated water rises above physical top of aquifer water under pressure Unconfined Aquifer water table level defines top of saturated materials water at atmospheric pressure only

Aquifer storage coefficient – Water yield increases per foot of drawdown when an aquifer converts from confined to unconfined Unconfined Aquifer Confined Aquifer Dewatering of Aquifer Release of Aquifer Pressure

Change in Aquifer Drawdown when well goes from Confined to Unconfined – Well A-1

Change in Aquifer Drawdown when well goes from Confined to Unconfined – Well A-3

Estimating Lifetime of the Existing Wellfield Lower ground water levels will eventually decrease production of individual wells New wells will be needed to meet existing peak demands Timeframe of existing wellfield is estimated using in-well measurements plus regional modeling Regional modeling based on South Metro model and pumping demands included in it

Percentage of Pumping in South Metro Model 5% 4% 19% 14% 1% 2% 10% 15% 7 CPNMD

Predicted Pumping by South Metro Providers, Year 2050 as simulated in South Metro Model – Average Scenario

Modeled Water Levels near CPNMD due to South Metro Regional Pumping - Average Scenario

Modeled Ground Water Levels, Year 2050 – Average Scenario CPNMD

Comparison of Highest and Average Pumping Scenarios, South Metro Groundwater Model

Potential Wellfield Production Affected By Decrease in Aquifer Water Levels - Improvements to wells A-1 & A-3 - Add well A-5 - Deeping/improving pumps - Drill additional wells - Obtain renewable supplies

What is CPNMD Doing to Address This? All entities are or will experience declines in well production CPNMD taking measures to address issue Improvement to Wells A-1 and A-3 in 2006 Bringing Well A-5 on-line in 2007 Potential for lowering/improving pumps Continued conservation measures Conducting IWRP to identify renewable supplies

Conclusions from Groundwater Evaluations Groundwater levels will decline regardless of CPNMD pumping CPNMD responsible for < 10% of the projected groundwater decline in the Castle Pines area CPNMD has less than 5 years before action must be taken to maintain existing production rates Drilling more wells: Needed to maintain pumping rates Very costly (~ $1.5M per well; current costs $540K per year) Does not achieve water sustainability

5. Water Supply Alternatives

Why Are Renewable Sources Important to CPNMD? Provides for the sustainability and reliability of CPNMD’s water system Protects and enhances property values Protects the quality of life

Why now, if groundwater supplies are sufficient for the near future? Pumping rates from wells will decline Investment in additional wells will be needed to maintain system capacity – higher costs Competition for surface water will drive prices upward Lengthy process to implement renewable supply The sooner demands on groundwater are reduced, the longer they can remain a viable part of CPNMD’s supply

CPNMD Water System Development The District is responsible for ensuring a safe, reliable and adequate water supply for their customers Goal is to identify the best mix of future sources and conservation measure to sustainably meet our community’s water needs Additional supplies needed to serve CPNMD Provide for perpetual and cost-effective water supply Seek partnering opportunities with other water providers

The Integrated Water Resources Plan will build integrated alternatives Renewable Sources Ground- water Conservation Buildout Existing Reuse Alternatives – combinations of supply options – basin by basin and statewide Organized around themes "Building Blocks" – examples shown here, may be some additional Combine into complete alternatives centered around a theme. Examples…

6. Water Supply, A Statewide Perspective FLIPCHART AGENDA FLIPCHART PARKING LOT Welcome and thanks to participants Thanks also to hosts ____________________ Self intro Intros: - CWCB Board Member - ______________ - Rod Kuharich – CWCB Director - Rick Brown – CWCB Project Manager - Basin Advisors - _______________ - LEGISLATORS? Other CWCB Board Members in attendance? - CDM team Review/refine agenda OK to interject – looking for input, feedback, dialog

Significant Increases in Colorado’s Population will Intensify Competition for Water

History of South Platte/Clear Creek Water Rights Cost and Availability

Municipal & Industrial Water Demand by Basin - 2000 - 2030 630,000 AF Increase

2030 Municipal & Industrial Water Demands and Gaps Yampa/White/Green North Platte South Platte Colorado Gunnison Dolores/ San Juan/ San Miguel Rio Grande Arkansas 107,600 AF 10,300 AF Identified Projects 404,300 AF Gap 107,800 AF

Sources to Meet Future Statewide Demands Water Conservation Water Reuse New Storage Trans-basin Diversions Agricultural Transfers Conjunctive Use of Groundwater and Surface Water

Front Range Water Providers actively seeking renewable or more reliable supplies for existing customers Halligan-Seaman Water Management Project Windy Gap Firming Project Denver Northern Firming Project City of Northglenn Aurora South Platte Project East Cherry Creek Valley Northern Water Supply Project Parker Rueter-Hess Reservoir South Metro Water Providers El Paso County Water Providers Colorado Springs Southern Delivery System

Potential Sources of Renewable Supplies Colorado River Basin Transbasin deliveries from Upper Blue River to Upper South Platte with Combined Storage and Pipeline Lower South Platte Fallowing program and water rights acquisition, gravel pit storage and pipeline Rueter-Hess Reservoir Upper Arkansas River Water rights acquisition with storage and pipeline to Upper South Platte Drainage Upper Cherry Ck and Plum Ck Water rights acquisition with storage & pipeline Upper South Platte Basin Water rights acquisition with storage and pipeline Lower Arkansas River Basin Fallowing and water rights acquisition with storage and pipeline

Storage Alternatives: Chatfield, Rueter-Hess

Conclusions and Observations CPNMD's water supply future is tied in with the South Metro providers CPNMD needs to support the efforts of all South Metro providers to find renewable sources Providers, such as Parker, ECCV and Centennial are involved with renewable water supply projects Other providers such as Castle Rock are actively seeking renewable sources CPNMD may partner with one or multiple entities to develop renewable supplies

Conclusions and Observations - continued Groundwater pumping by others cannot be controlled and impact CPNMD pumping yields The Integrated Water Resources Plan is a proactive approach to addressing CPNMD’s need for a renewable supply Increase water supply reliability Enhance property values Maintain quality of life

Conclusions and Observations - continued Renewable water sources will: Be needed in the future Become more expensive Become more scarce due to competition for the limited available supplies The longer CPNMD takes to act: Less renewable supply options Go farther for water More costly Partnership opportunities reduced or eliminated

7. CPNMD Project Financing Options

Financing Alternatives for Renewable Water Supply Development

8. Integrated Water Resources Community Participation Committee

9. Upcoming IWRP Project Activities and Community Information Meetings

For additional information or to provide comments: Contact: Castle Pines North Metro District James McGrady, District Manager 303-688-8550, ext. 11 jmcgrady@CPNMD.org Visit: the CPNMD web site at http://www.CPNMD.org