We provide high-quality water to our residents through two sources:

May-September - Well/Groundwater: We use our water wells, drawing from the Arapahoe, Denver, and Lower Dawson Aquifers. This water is treated at our own water treatment facility. Each fall, our operations team shuts down our Water Treatment Plant and activates our interconnect with Highlands Ranch Water.  

October-April - Renewable/Surface Water: We take full advantage of our renewable water resources through an agreement with Highlands Ranch Water. In 2010, the District purchased Hock Hocking (Park County, Colorado) and Upper Platte River rights to increase the community’s water assets to include surface water. This water is stored in Chatfield Reservoir, where CPNMD owns and has unfettered access to 1,006 acre-feet of storage capacity. Our neighbors to the north, Highlands Ranch Water, treat our renewable water, which we then pump through our existing interconnect pump station and pipeline into our water distribution system. This facility primarily serves CPNMD, the Town of Castle Rock and Castle Pines Metropolitan District (The Village at Castle Pines). Treated wastewater return flows are captured and used as the primary source of irrigation water for The Ridge Golf Course.

This annual switch in water sources not only helps to prolong our non-renewable water, a confined aquifer resource, but it also allows CPNMD to complete capital projects and do maintenance at our treatment plant that wouldn't otherwise be possible with the plant in full service. This year, we will be adding new filters to the plant. This is the last of many improvements needed for the plant to treat an additional 2 million gallons of water per day (7 million gallons total) to better meet current demand. You can read more about that here.

There are some differences in the water characteristics that some residents may notice...

• Hardness: Our renewable water is much harder than that of our deep well aquifers. Residents may notice things like water spots on dishes or fixtures.
   
• Taste: Some residents report that they notice a shift in the taste of the water. It is often described as "earthy, or metallic". This also has to do with the source water differences. The water is absolutely safe to drink and for all other uses. Highlands Ranch Water has been doing work at its treatment plant to help combat this aesthetic issue, and we do anticipate that this will be less noticeable in comparison to years past. 

For more information on these sources, visit our latest Water Quality Report to learn more about differences in water taste, hardness, and odor. 

Water Sources & Infrastructure

Most water in CPNMD originates from two Denver Basin underground aquifers, which include the Arapahoe, Lower Dawson, and Denver basins. These sources are the result of water rights that date back to the formation of the District. The District has 10 active water wells located in the community that are used (as noted previously) primarily in the summer months (May-October). 

This water is delivered to the CPNMD water treatment plant, which produces a current average of two million gallons of water per day, except in peak summer months when four million gallons of water per day is more common. Treated water is then stored in the District's two storage tanks, and supplied to customers on demand.