Meridian Services has a plan to save water

Tim Hunter, general manager of Meridian Services Metropolitan District, has a plan to save water in Meridian Ranch.In December, Hunter applied to Division No. 2 of the Colorado Water Court for a surface water decree allowing his district to capture runoff from rain and snow melt.The rooftops, streets and sidewalks in developments like Meridian Ranch create an impervious surface that prevents precipitation from soaking into the ground (also known as “alluvium”). Instead, it becomes runoff, Hunter said.”We want to capture a portion of that runoff, put it in a storage reservoir and use it to irrigate sports fields at Meridian Ranch Elementary School and Falcon High School, the golf course and other shared landscaping within the development,” he said.Drinkable water pumped from Denver Basin aquifers is currently being used for watering those areas.Last year, MSMD pumped 25-acre-feet of water out of Denver Basin aquifers just to water the two school sports fields; 55-acre-feet to water landscaping; and 300-acre-feet to water the golf course, Hunter said.It adds up to 380-acre-feet or 97,755,300 gallons of water taken in one year from a finite water source that residents in eastern El Paso County rely on for drinking water.Hunter said he wants to build a 55,000,000-gallon reservoir to store runoff and use it to water landscaping.”Meridian has thought about this for a lot of years,” Hunter said. “We already have the purple pipe for non-potable water at the two schools, and all our landscape areas are being built with purple pipe and sprinkler heads.”When the reservoir is built and filled, we’ll be able to switch off of potable water, irrigate with runoff and reduce our need for Denver Basin water.”However, will the storage of runoff that would otherwise flow downstream from Meridian Ranch take water from individual well owners south of the development?It’s a possibility as the plan stands now, said Dave Doran, president of the Upper Black Squirrel Creek Groundwater Management District.Meridian Ranch is located near the headwaters of the Upper Black Squirrel Creek basin – an area that’s crucial for recharging the alluvium, Doran said.There are many downstream alluvial well owners, and some might not even know if they have an alluvial well. Any well up to about 200-feet deep could be affected by the current version of MSMD’s plan, he said.Hunter disagreed. He said the small amount of runoff that would be captured from Meridian Ranch’s impervious surfaces would otherwise infiltrate the ground.A 1987 Colorado Geological Survey study estimated that only 4 percent of precipitation is absorbed by the alluvium, he said.It all makes sense, Hunter said, citing two reasons:

• In winter, when major snow storms are followed by warm days that melt the snow quickly, the melt runs off because the ground is frozen.
• In summer, when it rains after weeks of no rain, the ground is too dry to absorb the water quickly, and it runs off.

“By irrigating in the summer with runoff water, we’d be putting water back into the ground in a controlled way so it can seep in slowly,” he said.Hunter said he would like to do more with runoff water, such as building a surface water treatment plant that could be used to supply drinking water for MSMD’s customers.He would also like to do an aquifer storage and recovery system where treated surface water is pumped back into the Laramie-Fox, which is the Denver Basin aquifer that currently supplies drinking water to Meridian Ranch.”An ASR system would lessen the demand on the Denver Basin aquifers even more than irrigating with captured runoff, but that’s 20 years away at best,” Hunter said.”If this proves up and there’s enough runoff water to capture, we can supply customers with clean, potable drinking water and shut off our wells completely.”It’s not an impossible idea.Highlands Ranch has been operating an ASR system using spring runoff to service its customers and recharge the Arapahoe Denver Basin aquifer with excess water for eight to 10 years, Hunter said.”We’re not trying to harm any of the systems or take water from anybody. Water is a precious commodity,” he said. “The more we can save it, the better we’re all going to be, not just Meridian Ranch, but the whole Falcon area.”Doran said he thinks MSMD should be required to replace the runoff water it will store in its reservoir.”This is an over-appropriated basin and (they should not be given) new alluvial water rights unless they can come up with some kind of water to replace 100 percent of what they deplete,” he said.The UBS district and six others, including the Woodmen Hills and Paintbrush Hills metropolitan districts and the state engineer, have filed objections to MSMD’s plan, Doran said.Now it’s up to the District 2 Water Court to decide.More information is available by downloading a document from www.courts.state.co.us/Courts/Water/Resumes/Div2/resume12-2010.pdf and searching for Case No. 10CW95.