Observers say Grand Lake as clear as it’s been in 50 years
Grand Lake, CO Colorado
GRAND LAKE – The Northern Colorado Water Conservancy District is not pumping through Adams Tunnel until Sept. 6, and water clarity advocates are so far pleased with consequences.
“The clarity has so much improved over anything we’ve seen in August over the past 50 years,” said Three Lakes Watershed Association President Canton O’Donnell of Grand Lake. The 250-member organization has advocated for better water quality in Grand Lake for at least 20 years.
O’Donnell’s observations during a recent annual sailing regatta on Grand Lake are backed up by a Three Lakes Clarity Monitoring Report for July, which shows improvements in clarity throughout the month. Clarity in Grand Lake reached greater than 13 feet, a far cry from a 2007 reading of 4.8 feet in late summer.
The problem “everyone agrees on,” O’Donnell said, is the shallowness of Shadow Mountain Reservoir. Water delivered to northeastern Colorado to support communities and ranches is pumped through Shadow. Average residency for water in Shadow is about a month, during which the water heats up and produces algae, weeds and sediment brought through the canal into natural Grand Lake.
The monitoring program through the Grand County Water Information Network – which shares data with the U.S. Geological Survey, the Bureau of Reclamation and the Northern Colorado Water Conservancy District – analyzes weather and Secchi depth readings in lakes including natural Grand Lake and the connected Shadow Mountain Reservoir.
O’Donnell and others concerned about the diminishing lake quality in Grand Lake are hoping the latest data supports finding an alternative to pumping water through the lake.
“We are now convinced that the best possible remedy for Grand Lake and Shadow Mountain Reservoir is to not take any water directly into (Adams) Tunnel, but to have all of the natural flow go west-south to Shadow Mountain Reservoir dam, and then return it to (Adams) Tunnel via a pipe of some kind. This year is proving our case,” O’Donnell said.
“We all want clarity, there’s no question about that,” said Northern Colorado Water Conservancy spokesperson Brian Werner.
But Werner said the water delivery agency is holding out for results of all water quality studies, including an appraisal study – a federally initiated study through the Bureau of Reclamation that may serve as an umbrella for all data collected and may give a recommendation for moving water to the Front Range.
The study is slated to be completed in 2012.
In the meantime, the agency must cooperate with a state narrative standard for the lake set in 2008, which dictates that stakeholders work together to try and determine the causes of limitations on Grand Lake clarity and explore actions to improve clarity.
In 2008 and 2009, Northern Water conducted two-week operational adjustments dubbed “stop pumps” to improve lake quality in late summer.
Although a stop pump was not planned for 2011 – prompting Grand Lake’s mayor, Three Lakes and the Greater Grand Lake Association to craft a letter to the U.S. Department of the Interior – thanks to above-average runoff this year, summer 2011 will see the longest window for a stop pump to date.
According to Werner, pumping ceased at the end of May, and a “ramp up” of pumping will not resume until Sept. 6. Natural flows traveling into Grand Lake to Shadow Mountain Reservoir have been around 20 cfs during this period.
“If operationally we can do things that don’t impact the water deliveries, we’re more than willing to look at that,” Werner said. Northern contributes about $800,000 to $850,000 a year to water quality studies on the West Slope, he said.
Grand County and the Town of Grand Lake are also strong supporters of efforts to improve the quality of both lakes, providing financial and political support.
The 13-plus feet (4 meters) of water clarity this year is equal to a numerical standard Grand Lake advocates sought in 2008 from the Colorado Water Quality Control Commission. The commission instead chose to use language to define a “goal” for the lake and deferred setting a numerical clarity standard for Grand Lake until 2014.
Although a long shot in terms of dollars and agency will, county officials have said a bypass of Shadow and Grand Lake may be the best way to deliver clear water through the Colorado-Big Thompson system.
And a bypass, O’Donnell said, may “provide all the customers of Northern with better quality water.”
Tonya Bina can be reached at 970-887-3334 ext. 19603
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