Wasco council adopts 25-year storm water master plan, flags Seventh Street and Holborn as priorities

The Wasco City Council on Tuesday voted to accept a final storm water master plan that lays out a 25-year capital improvement program and identifies immediate capacity priorities along Seventh Street and Holborn Street.

City staff deferred to consultant John Kular, who presented the plan via Zoom. Kular summarized the study’s scope — reviewing existing systems, modeling flows against a 25-year growth projection and recommending capital projects — and said the city’s system includes about 17 miles of storm drains, 24 ponds and sumps and a mix of public- and privately-operated facilities. “We reviewed the city’s existing information, their geographic information system, and incorporated that into a civil storm model,” Kular said.

The plan found that 18 of 24 ponds meet the county’s five-day/10-year design criteria; 22 of 24 pass when evaluated against a 1% (100-year) rainfall event using current NOAA values. Major recommendations include constructing a new retention pond northwest of the primary retention pond adjacent to the wastewater treatment plant, replacing a diesel pump with an electric/baseline pump at a west-side detention pond and regrading pond drains to improve operability. Kular told the council the highest-capacity shortfalls are “on the Seventh Street corridor from the wastewater treatment plant to Redwood Drive and on Holborn Street from Central Avenue to Palm Avenue.” The plan prioritizes projects that protect schools and busy pedestrian corridors.

Resident Michael Dela Torre pressed staff on where pond and sump discharge ends up and who is responsible for maintenance. Kular and city staff explained that many sumps are terminal, designed to infiltrate stormwater into the ground within days, while an older system conveys runoff to a detention pond at Westside Park and onward to a terminal pond by the wastewater treatment plant; that terminal pond has a pump system that can split stormwater over leased farmland. City staff advised residents with maintenance concerns to contact Public Works.

Councilors asked about the plan’s timeline and standards. Kular said projects were spaced over 25 years with the large retention pond as a top priority; he noted the plan used current NOAA rainfall statistics and that the 1% storm volumes have increased compared with earlier studies. The council adopted a resolution authorizing the city manager to accept the final storm water master plan.

The resolution passed on a 4-0 roll-call vote with Council Member Martinez absent.