Gene Reetz, with the Audubon Society of Greater Denver, points toward areas that will be submerged under plans to expand the reservoir at Chatfield State Park. [CPR/BMarkus]

This holiday weekend, many Denverites will be headed out to Chatfield State Park, a popular destination for those looking to get out on the water and see a little nature. But some say that experience is in danger. Local water providers want to expand the reservoir to meet the demands of a fast growing population.

On a recent weekday morning, John Noble and his son Malcolm throw a frisbee around near a picturesque wooded corner of Chatfield State Park, just a quick drive from their condo, which doesn’t have a yard for Malcolm to play in.

“This is our park,” said Noble, “so this is our playground, for the little guy and for us.”

Noble has heard this and other parts of the park will be submerged if the reservoir is expanded, and he’s not thrilled about it. 

“We’re disappointed, because as I say it’s like our park.”

People like Noble have until Sunday to comment on the expansion. Most aren’t even aware of the impact it could have, according to Polly Reetz, a volunteer with the Audubon Society of Greater Denver. She says it’s not just recreation that will be disrupted. More than 375 different bird species have been spotted at Chatfield.   

“The National Audubon Society has designated this an important bird area,” Reetz said. “That’s a formal designation they use for areas that have particular value. They don’t just give it out free of charge.”

She stands in the shade of a few of the towering cottonwood trees some of those birds call home - trees that will have to be removed to accommodate more water.

Her husband Gene, also an Audubon volunteer, says the park as we know it is in danger. He even has a bumper sticker on his car that reads “Save Chatfield Park.” 

“The quality of the recreational experience will be vastly different,” he said. “The habitat for wildlife will be lost, so the whole aspect of the park and its values will be dramatically changed.”

The project’s backers don’t believe that.

“It’s not in danger,” said Rick McCloud with Centennial Water and Sanitation District, one of the lead proponents of the reservoir expansion. “It’ll be changed by this project, but it’ll still be a wonderful recreation and wildlife area.” 

He says 37 other alternatives were studied, and the Army Corp of Engineers has determined this project is the best way to help bring desperately needed water to residents and farms with minimal environmental impact.

“No project has no impacts,” said McCloud. “We’re being, we think, very appropriate in the way that we’re responding to those impacts and mitigating them, covering our divots so to speak.”

If the project gets the final OK, McCloud says more than $40 million will be spent just moving recreational facilities like trails and beaches. New trees will be planted for the ones that have to be removed to accommodate more water.

Not all environmental groups think the project is a bad idea. 

“There are no free lunches in terms of meeting the Front Range’s critical water needs,” said Rob Harris, with Western Resource Advocates. He said expanding existing reservoirs like Chatfield is better than building new ones. 

But the Audubon Society of Greater Denver says the scope of the project isn’t well understood by other environmental groups, or the public.  The group says once people see acres of trees around the reservoir being ripped out, it’ll be too late.  

“It’s something that you really can’t replace,” said Audubon volunteer Gene Reetz. “Even though the project proponents have said that they would mitigate all the impacts, you really can’t replace 100-year-old cottonwood trees, and that’s something that will be lost forever.”

A decision on the expansion could come as soon as the end of the year.