Technical
Memorandum
1204 E Street ● Marysville, California 95901 ● Tel.: 530.742.6485 ● Fax: 530.742.5639 To: Jeramy Chapdelaine - Public Works Director
From: John Mallen, PE, PLS – Consultant City Engineer
Date: March 10, 2026
Subject: Emergency Repair of City of Marysville Gravity Sewer Main Oak Street 4th to 5th This technical memorandum was prepared to address the emergency repair needed for the City sanitary sewer main located in Oak Street between 4th and 5th Streets. The sewer main roughly 100 feet south of 5th Street was determined to have a blockage and crews were unable to push through it with all equipment attempted to get through or get a good video inspection of the blockage. The main was exposed after the location was determined and it was discovered damage to the main and the adjacent sewer lateral was damaged with a missing segment and large void under the street around it. With the blockage removed, additional sections of the sewer main showed damage on inspection and the walls of the pipe showed signs of deterioration.
To remove the hazard of the sewer main backing up and the void collapsing in Oak Street, the sewer main and lateral will need to be repaired at the connect and the void cleaned up and slurry backfilled. To remove the potential of future blockages and failures the sewer main should be repaired where already failed at additional nearby locations and a protective liner installed in the remaining portion of the sewer main segment. Based on the depth of the main and the amount of overlapping work, it is in the City’s best interest to complete the additional replacement of the main and installation of the lining at the same time the lateral repair and damaged area of the already exposed is repaired.
The contractor has estimated the total cost for all the work at $205,200 (verbal estimate pending written proposal) with $3,500 of that cost being attributed to the property owner lateral repair (anticipated cost recovery from responsible property owner). The scope includes Pipe Burst Replacement (Manhole to Manhole) and replacing approximately 130 linear feet of 8‑inch sanitary sewer main withing that segment using HDPE pipe. The price is reasonable for the amount of work already performed during discovery and required to complete the scope of work.
I recommend proceeding with the emergency repair as soon as possible.
Sincerely,
John Mallen, PE, PLS