Heavy rains from Thursday, Dec. 19, led to tough commutes through Renton Friday morning. For some drivers, they found themselves driving deep into standing water.
The city closed portions of Park Avenue North, Hardie Avenue Southwest and Southwest 43rd Street after flooding created vehicle risks for those roads, and some vehicles required towing to get out of the water. The roads re-opened to traffic later that afternoon.
Renton Police Department tweeted out asking drivers to be careful and not drive through standing water as is could be deeper than it appeared.
Public Works Administrator Gregg Zimmerman said in his 30 years with the city he’d never seen the flood volumes they dealt with along Southwest 43rd. And it has been many years since Park Avenue had received that sort of flooding.
The city’s street drainage design is meant to handle heavy rains up to a 25-year storm event, meaning flooding is expected on storms as large as ones expected to happen an average of once in every 25 years. But drainage issues, root intrusion, pipe cracks and short and intense storms can all lead to flooding.
Zimmerman said many residents help the city, in conjunction with the work of its street sweepers, by raking leaves off catch basins near their homes. This is a simple way to solve drainage issues when a storm hits. The city regularly inspects stormwater collection systems with internal TV cameras, to see if any root intrusion or pipeline cracks have partially filled the pipe, but Zimmerman said they are difficult to maintain. Older drains also don’t have the same 25-year capacity as newer drains that follow the city’s updated design standards.
“We have made large improvements over the years, but we still have flooding episodes when we experience very strong precipitation events like we’ve been dealing with today,” Zimmerman stated in an email.
For any problem streets that experience flooding more often, Zimmerman said the city adds more drainage capacity using capital improvement projects, and provide additional maintenance to these streets.