Re:Thames Tideway Tunnel super sewer completed
by ryansouza on Wednesday March 27, 2024 @03:29PM
(#39843529)
Hi Ian!
Portland has also been working on the “next steps” pointed out in this article. Street bioswales provide absorption and holding capacity. Downspout disconnection programs and new build codes drain rooftop rain locally on the property or out to the street instead of directly in to the sewers.
I think we have an easier time due to our lower density. Most lots have decent amount of exposed ground for rain infiltration, and the area has well draining soil. Tougher for cities more tight and built up. I think Seattle codified water management before the latest building boom so hopefully they will do alright too!
In Portland, we did similar combined sewer pipe. But they didn't size it to handle the largest rainfall. The sewers still overflow a couple of times a year, but it is much better than dozens of times. Especially since it now only happens in the winter when no one is using the river. It would have cost a lot more to handle peak rainfall. It is already expensive, sewer costs twice as much as water here.