While securing local water rights and conserving existing water supplies are important, the Town's plan also includes participating in regional partnerships to further bolster the community's water future. In particular, the Legacy Water Projects include WISE Water and the Box Elder projects. They are also known as the alternate source of supply projects. These projects are designed to import water from Denver, Aurora, and other water rights the Town is purchasing on the South Platte River north of Denver. Additionally, Castle Rock has also filed for a junior water right on the South Platte River in far northeastern Colorado with the intent to import this water in conjunction with a partnership with Parker Water and Sanitation District.
South Metro Water Supply Authority
The South Metro Water Supply Authority (SMWSA) has been instrumental in developing opportunities for smaller Front Range water providers to partner with larger ones, such as Denver and Aurora. The authority is also implementing studies and projects as identified in the Regional Water Master Plan. SMWSA was instrumental in the negotiations with Denver and Aurora for the WISE project.
In 2009, Castle Rock Water became part of the WISE Partnership. That partnership of ten South Metro organizations signed agreements to import renewable water from Denver and Aurora. To date, the Town has invested over $52 million into water infrastructure to be able to receive water into Castle Rock's system. Water from the WISE project began flowing to Castle Rock in 2018. The WISE water infrastructure is important in that will not only allow Castle Rock Water to import WISE water but also bring water from the Box Elder project in the future.
Box Elder project
Castle Rock Water has invested about $29 million into the property purchase and water rights in the South Platte River Basin, north of Denver in Weld County. As of 2021, the Town has purchased 2,260 acre-feet of water rights for the project out of a target of 2,500 AF. The Box Elder well field in Weld County will be used to divert these water rights and we are working on partnerships to treat and pump the water back to the Town.
Securing the remaining water rights for this project will be a focus in the next couple of years. Many of the details of the Box Elder project are still in the planning stage, but with the goal to bring water from this project to Castle Rock sometime around 2030. The Box Elder project is part of the alternative sources of supply projects.
Castle Rock Water is partnering with other communities to share in the costs and resources of imported renewable water. The Smoky Hill tank and Quebec Street Treatment Plant are two of several WISE assets which are owned jointly with the members of the South Metro Water Supply Authority, and Rueter-Hess Reservoir will store excess imported water for several communities.