Efforts start to restore Grand Lake’s clarity
GRAND LAKE – Once known for its clear, blue waters, Grand Lake was turned green this summer by algae, prompting action by people distressed about the future of the state’s largest natural lake that is also a major conduit of water for the Front Range.In the summer, the algae levels were so high that a first-ever drinking-water ban was imposed. Cooler fall weather has killed the toxic algae and the ban has been lifted, but area residents want changes so they don’t face the dilemma again.The Colorado Water Quality Control Commission will hold a hearing next month to start gathering information on whether a clarity standard for the lake should be set.And the Northern Colorado Water Conservancy District, which pumps water from warmer reservoirs through Grand Lake to the Front Range, is studying if it can change operations to help clear up the lake.It will take the cooperation of nearly a dozen county, state and federal agencies to change the way the lake is managed.Lake previously had perfect clarityThe lake on the western side of Rocky Mountain National Park, about 100 miles northwest of Denver, is a glacial pool that was once one of the clearest bodies of water in North America. In the 1940s, scientists routinely reported clarity at depths of more than 30 feet.People reported clarity of less than 3 feet during the summer when the water was pea-soup green.”Today the lake is a disaster,” said Canton O’Donnell, a Denver businessman whose family has vacationed in the Grand Lake area since the 1890s.One of the issues is the warmer water piped through Grand Lake from Lake Granby and Shadow Mountain Reservoir as part of the federally owned Colorado Big Thompson Project, run by the Northern Water Conservancy District. The water goes through the Alba B. Adams Tunnel to the Front Range, where it supplies about 750,000 people.The warmer water stirs Grand Lake and brings heavy loads of nutrients. The combination of warm water and nutrients spur the growth of algae carried in from Shadow Mountain.The water district is studying possible ways to change operations, including periodically silencing the massive pumps that ship water through the lake to determine how the lake responds. It’s also studying the feasibility of another pipeline to take Grand Lake off the system altogether.While the district and other agencies say they’re ready to begin restoring the lake, they believe that they’re not the only culprits. They point to years of development around the three lakes and pollutants from runoff and sanitation systems.Area residents don’t dispute that, but say new water sanitation systems have solved most of those problems. They say they’re also working with communities to make sure everyone contributes to the rehabilitation effort.Utilities are concerned that setting a clarity standard for the lake might limit their ability to move and deliver water and area developers worry that it will affect their activities.