Chatfield Reservoir Reallocation Study

GENERAL QUESTIONS

What is the Chatfield Reservoir Reallocation Storage Study?

It is a federal/ state study by the U.S. Army Corps of Engineers (Corps) in cooperation with the Colorado Water Conservation Board (CWCB) that includes a Feasibility Report and Environmental Impact Statement (known as an FR/EIS) to assess the viability of reallocating some of the storage space in Chatfield Reservoir from flood control to joint flood control and conservation purposes, and to assess potential recreational and environmental impacts associated with such a reallocation.

What is a reallocation?

The concept of reallocation means to convert space from one type of storage use to another.  In this case, reallocation would re-designate water storage space in Chatfield Reservoir that is currently reserved exclusively for flood control purposes to storage space for joint flood control and conservation purposes. This is achieved by designating a higher elevation for the top of the existing multipurpose-conservation pool, effectively increasing capacity for multipurpose water.  The expanded multipurpose pool would be re-designated as the "joint flood control-conservation" pool. 

Why is a reallocation being requested?

Many regional providers have secured rights to surface water in the South Platte River and Plum Creek to decrease their dependence on non-renewable underground aquifers.  Fifteen such water providers are looking for a storage solution to capture those water rights when runoff flows in Plum Creek and the South Platte are high, and store that water until needed, which is critical to providing reliable water supplies in Colorado's semi-arid climate.  Additional storage in Chatfield Reservoir for multipurpose water, achieved through a reallocation, could help those providers meet demand for municipal and industrial water supplies in response to population growth in the region, as well as assist agricultural water users in meeting their water demands.  A reallocation also could have benefits to recreation and fishery habitat protection and enhancement purposes.  

Why is the study necessary?

Corps regulations require the preparation of a Feasibility Report to support the request for reallocation of storage space in one of their reservoirs.  In addition, the National Environmental Policy Act (NEPA) requires that federal agencies prepare a detailed study, known as an Environmental Impact Statement prior to undertaking any major project occurring on federal lands, requiring federal permits, or receiving federal funds that could potentially impact the environment. 

How long has the study been underway?

Planning meetings on the reallocation were first held in 1994.  Corps regulations on reallocation require an initial formal study, called a Reconnaissance study, which was initiated in 1996. The CWCB signed a Feasibility Cost Share Agreement (FCSA) with the Corps in 1999, and the study began shortly thereafter.  Several challenges related to federal funding, policy changes and contract negotiations have led to a schedule that is much longer than originally anticipated.

When will the study be completed?

A specific completion date is not known at this time.  The Corps is currently working to produce a draft of the FR/EIS, which is anticipated to be released in 2010.  After the required public comment period, the study will undergo revisions and be released as a Final FR/EIS.  Then the Corps will issue a Record of Decision on whether a reallocation would be feasible.  The Final FR/EIS and ROD are anticipated in 2011.

How much will the study cost?

Currently, the total study cost is expected to be on the order of $5.75 million, and is based on a 50:50 funding split between federal (Corps) and non-federal (Colorado Water Conservation Board with local water providers) interests. 

How is the study being paid for?

The study is being funded by federal and state budget appropriations and by local water providers. 

QUESTIONS ON IMPACTS

What impact would a reallocation have on the flood control reservoir?

The reallocation of storage space in Chatfield Reservoir could increase the water level up to 12 feet higher when water is stored during non-flood conditions. Water level fluctuations could increase both in magnitude and frequency. 

What impact would a reallocation have on the dam?

The reallocation of storage space in Chatfield Reservoir would take place with no negative impacts on flood protection for downstream properties. The reallocation would not require any physical improvements or modifications to the dam, spillway, outlet works, or other related structures.  

What impact would a reallocation have on Chatfield State Park?

Recreation facilities around the reservoir could be impacted/inundated by higher water levels, requiring a change in the operations of the reservoir and the construction and/or relocation of infrastructure, such as roads and facilities. Recreational activities and facilities at Chatfield State Park may be impacted temporarily or put on hold for public safety during construction and/or relocation of infrastructure.  Environmental factors, such as water quality, fish and wildlife habitat and wetlands, may be impacted, requiring mitigation (both on-site and off-site as necessary).

Who will pay for any changes to Chatfield Reservoir and State Park?

The implementation of all aspects of the reallocation effort would be paid for by the non-federal interests. The CWCB has $2 million available as seed money as approved by the Board and the General Assembly in Senate Bill 07-122.  If the reallocation is approved, the 15 water providers will enter into a contractual agreement (or agreements) with the CWCB regarding payment of the project implementation costs.  Such implementation costs include, but are not limited to, storage costs, environmental mitigation and recreation modification.  

Will additional land be acquired to add more space to the park if a reallocation is approved?

Environmental mitigation activities may take place outside of the current park boundaries, as needed on a case-by-case basis, to meet the mitigation requirements specified in the Record of Decision (ROD).  Any opportunities for land acquisitions will be examined by the non-federal interests that are accountable for mitigation, taking into account land costs, patch size, connectedness, potentially-benefiting species and other factors to determine its viability and priority as a mitigation option.

SECONDARY QUESTIONS

Are water providers considering developing water storage somewhere else?

Yes, alternative storage options are being considered in the FR/EIS, including the construction of new reservoirs and the use of gravel pits.  The water supply needs of most of the water providers will not be fully satisfied by the reallocation project.  Therefore, the search for additional water supplies and water storage will continue with or without the reallocation project.

Has a decision already been made about reallocation at Chatfield?

No.  The Corps expects to release a draft of the study for public comment in 2010.  After the public comment period has expired, the Corps will review and take into consideration all comments provided on the Draft.  After that process has been completed, the Corps will release the final FR/EIS and complete its record of decision (ROD) on any action at Chatfield Reservoir.

Is the water currently in Chatfield Reservoir used for drinking?

Yes, Denver Water currently makes use of its conservation storage space in Chatfield Reservoir to store municipal water supplies for drinking.  It treats the water to meet national drinking water standards before distributing it to consumers.

Will there be opportunity for the public to comment on the study?

Yes.  Members of the public will be invited to share their comments on the Draft FR/EIS, which is expected to be released in 2010.  Public meetings will be held to present information about the study and accept comments from the public.  During the comment period, public input will be accepted by mail, phone and email.  Any comments received will be formally documented and considered during preparation of the Final FR/EIS.   

How can I find out more information and get updates on the study's progress?

Visit the Study Web site at www.chatfieldstudy.org or pick up a study flyer at Chatfield State Park's gates.  Questions and comments can be directed to our toll-free hotline number at 1-866-643-5875 or by email to info@chatfieldstudy.org.