Basalt to see ‘generational’ sewer replacement near Fryingpan River

The Basalt Sanitation District will replace a sewer main over the next several months to update outdated equipment and reduce water infiltration into the line from the Fryingpan River. 

Beginning on Nov. 3 just uphill from the intersection of Midland Avenue and Two Rivers Road, the sanitation district will replace 342 feet of outdated clay sewer pipe with PVC pipe. The replacement, which will be constructed underground along the edge of Two Rivers Road, includes a segment running under the Fryingpan River. 

The district hopes to conclude construction this coming spring.

Basalt Sanitation District Manager Ian Quillan said this sewer main was installed in the early 1970s, and the replacement will help water “infiltration,” where ground water — or the river water moving underground in the area of the Fryingpan River — seeps through cracks into the sewer line, which he said is a common issue with sewer systems.

“The river water is getting into the pipe,” he said.

Water infiltration takes up unnecessary capacity and energy as it forces the treatment plant to process the additional water, according to Quillan.

“It’s just more wear and tear on the machinery, pumps and valves,” he said. 

The district has not seen any indication that sewage is leaking out of the pipe after monitoring it for about a year, Quillan said. The groundwater’s hydrostatic pressure, or the stationary pressure it exerts, is higher than the pressure inside the pipe, which pushes the groundwater through cracks into the pipe, rather than sewage through cracks into the groundwater.

He added that the district will coat the segment of the new PVC pipe running underneath the Fryingpan with concrete to account for catastrophic events like floods.

“The hope would be (that) the pipe would survive,” Quillan said, adding that the district aims for the total replacement project to last for the next 50 to 75 years. 

“Its a one in a generation project,” he said. 

The replacement, Quillan said, will also help ensure the the Fryingpan and Roaring Fork rivers keep their Gold Medal status, a Colorado Parks and Wildlife designation for Colorado trout streams with “exceptional opportunities to catch large trout,” according to CPW’s website. Just three lakes and 322 of Colorado’s 9,000 miles of trout streams are currently awarded Gold Medal status, according to CPW.

The sewer line replacement will cost a total of $1.65 million, which the district will pay for primarily using its general and reserve funds. The district did, however, secure a $250,000 grant from the Colorado Department of Local Affairs to help finance the project. 

Quillan does not anticipate any road or lane closures on Two Rivers Road during the project, although said parking along the side of the road could be impacted. 

Basalt Interim Town Manager Doug Pattison said “we’ll find out” to what extent the construction will impact parking, but noted that during shoulder season — right now — there is plenty of parking in town. 

“Work needs to be done, and it may affect it,” Pattison said of the project’s impact on parking. 

Construction will pause for Thanksgiving as well as for a two-week period during Christmas and New Years, according to a Basalt Sanitation District press release.

Skyler Stark-Ragsdale can be reached at 970-429-9152 or email him at sstark-ragsdale@aspentimes.com.