The Pagosa Area Water and Sanitation District (PAWSD) announced Wednesday morning that last weekend’s rain-on-snow event is causing flooding and sewer issues in the area.
“Rain on Snow (ROS) events occur when rain falls onto an existing snowpack,” a press release from the agency explains. “The result is runoff that includes both rainfall and melted snow, which can overwhelm drainage structures causing flooding. This flooding saturates the soils, enters basements and crawlspaces and infiltrates the sewer system.”
It further notes that the ROS event has led to regional flooding in the community, and PAWSD crews are monitoring the situation and assuring pump stations are working at their highest capacity.
PAWSD has also reported the overflows to the Colorado Department of Public Health and Environment, it adds, and Archuleta County crews are working to unclog culverts and maintain drainage structures to reduce the inundation of flood waters.
“PAWSD and Archuleta County realize this is a terrible situation and will only be exasperated by the upcoming storms,” it notes.
The press release also lists ways that home and business owners can help reduce infiltration (groundwater that seeps into sewer pipes) and inflow (stormwater that quickly flows into sewers):
- Do not connect sump pumps to the sanitary sewer.
- Do not connect roof drains and gutters to the sanitary sewer.
- Do not connect foundation drains to the sanitary sewer.
- Keep all cleanouts capped, both inside and outside. This will help keep unwanted water out of the sanitary sewer system.
- Avoid planting trees/shrubs over your sewer lateral, as tree roots can damage sewer piping.
- Keep driveway culverts and bar ditches clear allowing snowmelt and precipitation to flow off your property and out of your neighborhood.
- Report clogged roadway culverts and bar ditches to the county.
If you live in an area that is prone to flooding and sewer backups, the press release notes that PAWSD recommends installing a check valve on your sewer service. Sewer service check valves can be purchased at plumbing stores or directly from PAWSD. These check valves allow sewage to flow only in one direction — away from your home.
It explains that if the sewer main becomes surcharged, the check valve will close and not allow sewage from the main to reverse flow up your service line and into the home.
“Keep in mind these check valves do need maintenance, over time solid materials can build up not allowing the check valve to operate correctly,” it reads. “These solids must be removed routinely to assure the check valve is protecting your home.”