U.S. Water News Online
AURORA, Colo. -- Aurora water officials have a plan to turn two high-country aquifers outside the Denver area into water bank accounts for the city. If approved, the projects would allow Aurora to pump water out of the aquifers in dry years, then replace it during wet years. This is overdraft protection for water in a city looking ahead to a growing and thirsty population, Aurora city officials say.
Some water experts call this form of groundwater recharge an innovative and environmentally sensitive solution for meeting water needs. With this technology, excess water can be stored in the aquifers instead of building huge new reservoirs.
The concept of recharging aquifers is not new. There are similar projects across the country. Orange County, Calif., has used the technology since the 1960s, and the Bureau of Reclamation has set up 13 demonstration projects in Western states. Congress has allocated up to $31 million for the recharge efforts.
Aurora's proposed projects are in Park and Eagle counties. The city is working with Colorado Springs on the project in Eagle County.
The Park County proposal would tap an aquifer containing about 16 million acre feet (A-ft) of water under the Sportsman Ranch, near Como. The water project was originally conceived by a geologist and a water attorney who purchased the ranch and water rights and then made feasibility studies. The city has hired the two-man team to guide the project through water court.
The city plans to take as much as 20,000 A-ft a year from the aquifer. Its total annual use at present is approximately 47,000 A-ft per year. It's too early to estimate the cost of the project, but city officials said their best guess is about $5,000 per acre foot, or about $100 million.
Preliminary plans call for the city to drill approximately 26 wells to tap the groundwater, which is found at a depth of 6,000 feet in some areas. The water would probably be discharged into fabricated streams or pipes, flowing about 70 miles until it reaches an existing city reservoir. From there it would be channeled to Aurora's water-treatment plant.
To recharge the aquifer, the city would divert water from nearby streams where it has water rights, to small ponds located where the aquifer is closest to the surface. Once there, the water would percolate slowly through the base of the pond into the aquifer beneath. Or the water could be injected into the aquifer through recharge wells.
Many of these details are still being worked out. In the meantime, it could take up to 10 years for the city to win approval from the state water court, and there are no guarantees it will be approved.
Return to the U.S. Water News Archives page
Return to the U.S. Water News Homepage