Basalt to begin sewer line replacement and repair this week

The Basalt Sanitation District is beginning repairs and replacement of sewage lines along Two Rivers Road and across the Frying Pan River this week. 

Stutsman-Gerbaz Earthmoving, a Roaring Fork Valley-based excavation company, began moving concrete barriers into place on Monday to mark the construction territory.

The repair was prompted by water infiltration from the Frying Pan River and the ground due to aging clay pipes along the water line and under the river. In total, around 342 feet of clay pipe are planned for replacement with PVC pipe. 

To perform the repair, sewage lines need to be diverted and pumped, so that people and businesses “upstream” of the sewage repair do not lose service. 

“There’s a bypass pump that gets put into the nearest upstream manhole,” Basalt Sanitation District Manager Ian Quillan said. “They have fused a set of pipes that will run along the ground and continue to convey that sewage past the project area. They’ll discharge the water into a lower downstream manhole where it’ll go back into the regular sewer system.”

Later this winter, when the construction crews begin working on the river crossing, they will have to divert the river to work on the pipes.

“The contractor and our engineers have designed a series of coffer dams,” Quillan said. “We’re going to be laying that coffer dam halfway across the river, de-watering where we need to de-water, and then pumping that back. Then the remainder of the river will flow around the coffer dam.”

Construction in the area is not expected to impact traffic flows. However, parking may be obstructed due to construction equipment working on the side of the road. 

While water has been getting into the pipes from ground and riverwater, that does not mean that wastewater has been getting out. 

Quillan told The Aspen Times in October that the sanitation district performed testing to confirm that this was not the case, and found that the hydrostatic pressure of the groundwater in the area was higher than that of the pressure in the pipes, meaning water would only flow into the pipes rather than out. 

Water getting into the system has presented a problem because the increased pressure provides undue wear on downstream pipes and wastewater treatment infrastructure that will be treating a higher than necessary volume of water. 

According to the Basalt Weekly Manager’s report, the repairs are expected to conclude in early March 2026.