To help reduce the amount of storm water that flows into the sewers, Seattle Public Utilities (SPU) is building roadside raingardens along 28th Ave NW.
The future raingardens are still under construction and some of them are filling up with water during major storms like we had last weekend, and aren’t draining. “The swales have been filling up during the heavy rains and the water has been sitting in them for days without draining,” Nancy, one of the neighbors emailed us. “A few days ago there was a group of folks with clipboards and cameras having a meeting on the sidewalk and looking at the full swales.”
“The drainage capability of the rain gardens will improve when the all of the weirs are installed and the landscaping is planted, mulched and growing,” Christine Woelfel, SPU Project Manager Supervisor tells us. “At present, some of the bio-engineered soil isn’t draining as anticipated and we’ll replace it before the plants and mulch go in.”
Woelfel tells us that the inlets for many of the raingardens are plugged with sandbags to keep the water out during construction, and they’ve discovered that the seal isn’t tight enough. “All this rain is complicating the construction and we’ve needed to pump out the rain gardens to dry them out quickly so the contractor can get back to work as soon as possible to complete the project,” Woelfel says.
“Additionally, the water depth in some of the unfinished rain gardens was deeper than 6-inches,” Woelfel says. “Since 28th Ave NW is a main path for school children, we wanted to be cautious and not allow deeper water, even on a temporary basis, so we pumped them out. Once the construction is done the raingardens will drain normally and pumping will be unnecessary.” (Thanks Nancy for the email and photo of the city pumping the raingarden.)