Water agency may grant funds for temporary fix to antiquated Marysville drainage system
Jan. 15--Rains nearly overwhelmed Marysville's storm drainage system last year, which highlighted the city's need to improve its outdated infrastructure, a city official said.
The cost to implement temporary fixes while permitting is sought for a permanent solution is expected to reach six figures, but the Yuba County Water Agency is considering granting the city the needed funds.
"During the winter storm events in early 2017, pump stations were all pushed to their limits," said Jim Bermudez, director of Community Development and Services for Marysville, in a staff report. "Overall drainage was maintained, but revealed a fragile and antiquated system which could present future drainage challenges should the city experience an unseasonal climate event and/or hydraulic system failure similar to the Oroville Dam in the future."
The primary area of concern was at the city's Ellis Lake Pump Station (at the end of Ellis Lake Court), which uses a gravity line to allow water to flow from the lake out to Jack Slough when the river and slough levels are below an elevation of 53 feet -- generally during the winter season.
Last February, percolating water was discovered on the river side of the levee at the pump station. The pipe that conveys the water from the station to the slough, which has a gate to prevent backflow, wasn't working properly either. Rainfall continued throughout, causing water levels in the entire storm drainage system to increase.
That's when city officials had to make the decision to bring in temporary pumps to drain the system or else risk flooded walkways around the lake and water pouring from several manhole covers and drainage inlets throughout the city. It took more than week for the temporary pumps, running 24/7, to bring the water level down to its normal level.
Once water elevations receded for the winter, the original pipe at the Ellis Lake Pump Station was video inspected and found to have holes. It was eventually determined that the pipe through the railroad embankment and levee was deficient.
"The age, type of construction, and discovered issues with the pipe through the railroad embankment and levee made it clearly apparent that replacement or an interim design solution of the pipe should be a high priority," Bermudez said in a staff report.
A permanent solution was estimated to cost approximately $625,000, but would require permitting approval from Union Pacific Railroad, the Central Valley Flood Protection Board and the U.S. Army Corps of Engineers -- which could take years to navigate.
City officials plan on conducting the permanent solution eventually, but are looking at an interim fix in the meantime.
City staff came up with an alternative of using the existing pipe as a sleeve and welding a new pipe inside the existing one, with the annular space between the two being grouted.
"This will allow the city to use the pump station until a permanent replacement pipe can be permitted and installed," Bermudez said in a staff report.
The city collected bids for the interim project and the lowest -- Eaton Pump Sales and Service out of Woodland -- came in at $156,355.
Bermudez said the city is pursuing reimbursement for the work through the Federal Emergency Management Agency "as an extension of the temporary pumping since the permanent solution could not be permitted through the various relevant agencies during 2017."
Uncertainty remains whether FEMA will fund the project. However, YCWA officials expressed interest in partnering with the city to get the job done, Bermudez said, and are considering giving Marysville a grant in an amount not to exceed $175,000.
Bermudez said the grant and interim project would allow the city time to develop, permit, fund and construct a full repair to the entire drainage system -- estimated to cost around $1 million.
"YCWA is not seeking reimbursement from the city and should a condition arise which FEMA reimburses the city for this project, the agency prefers the $175,000 be used to fund a permanent design solution for Ellis Lake," Bermudez said in a staff report.
The agency's board of directors will consider approving the grant at its meeting Tuesday, which starts at 9 a.m. and will be held at the Yuba County Government Center -- 915 Eighth St., Marysville.
If approved by the agency board, Marysville City Council members will discuss authorizing the use of the funds and award a contract to Eaton Pump Sales and Service later Tuesday at their meeting, scheduled for 6 p.m. at City Hall -- 526 C St., Marysville.