Chatfield Reservoir

Chatfield Reservoir

The expansion of Chatfield Reservoir will increase the region’s available water supply and decrease our reliance on nonrenewable groundwater.

Increasing renewable supply

The South Metro Region has historically been dependent on non-renewable groundwater, and we know that will not meet the water demands for generations to come. To help overcome this future supply shortage, and to create a secure and sustainable water future for current and future residents and businesses, water providers must work towards a regional goal of diversifying and increasing renewable water supplies.

Storage is an important component of renewable water supplies.

Currently, much of the space in Chatfield Reservoir is used for flood control. However, the US Army Corps of Engineers (USACE), who owns the reservoir, determined that Chatfield Reservoir can actually reallocate 20,600 acre feet of water storage without compromising its original flood control function. The additional storage in the reservoir will be used by several municipal water providers and agricultural organizations to meet their needs along the lower South Platte River.

The Chatfield project participants currently include: Colorado Parks and Wildlife, the Colorado Water Conservation Board, Center of Colorado Water Conservancy District, Central Colorado Water Conservancy District, Mount Carbon Metropolitan District, and three South Water Metro members. After 20 years of careful planning, collaboration, and a lot of hard work, the project received a Federal Record of Decision from the USACE in May of 2014. In October of 2014, a Water Storage Agreement was signed with the State of Colorado and USACE, giving the project participants the official green light to move ahead with the reallocation. The nine participants are working on necessary environmental mitigation and recreation modifications that are expected to cost approximately $134 million.

Chatfield Reservoir

The South Metro Water Members in the Chatfield Reservoir Reallocation Project are: Centennial Water and Sanitation District, Castle Pines North Metropolitan District, and the Town of Castle Rock. At the end of 2014, the three Chatfield-South Metro Water members signed a new Participation Agreement to recognize the importance of the project to the region, and to establish that South Metro Water will provide assistance and support at the request of the three participants when needed.

For more information, please visit or the Colorado Water Conservation Board and the US Army Corps of Engineers Chatfield pages.