Upgrading Sewer Infrastructure in Maple Valley, WA

Keeping an entire neighborhood's sewer service running while upgrading the system underneath it takes careful sequencing, and that was the core challenge on this Maple Valley project. The work sat inside a constrained right-of-way corridor, with paved roadway, residential frontage, and existing utilities already occupying the site, all while an active sanitary sewer line kept running through the middle of it. Traffic control and utility and power-pole protection had to stay in place throughout, on top of everything else the site already demanded.

Our team installed a 54-inch manhole, a 48-inch manhole, roughly 36 linear feet of 6-inch PVC sewer pipe, and a right-of-way cleanout — using Olympic Foundry MH30A D/T rings and covers with Kor-N-Seal manhole connections — along with the excavation, backfill, and pavement restoration needed to tie it all together. Sequencing was the biggest factor throughout, since the new connections had to go in without interrupting existing sewer service, and close coordination with the utility district and other affected parties kept inspections and construction on schedule. The full project wrapped in about a week and a half, bringing the sewer infrastructure up to Soos Creek Water & Sewer District standards at a cost in the $80,000 to $100,000 range.