Question: What can be messier than having the Green River run through your living room this winter?
Answer: Having Metro’s brown river running through you living room this winter.
A manhole cover in Des Moines Iowa get’s displaced by floodwater.
Photo by Jake Bauma (some rights reserved).
With the damage to the right abutment of the Howard Hanson Dam, there has been lots of talk about homeowner’s insurance, levee improvements, sandbags, pumps, and other precautions that cities, businesses and homeowner’s might take to minimize damage if the Green River floods.
I have not seen as much focus on another key safety device that would be highly recommended for many homeowners: sewage back-flow prevention valves.
Schematic of simple sewage back-flow preventer. Image thanks to City of Fort Wayne, Indiana
If your home is on the flat-lands, surrounded by hills, it may be a good candidate for a backflow prevention valve. This would be especially true if your home is less than ten feet above the elevation of the Metro treatment plant in Southwest Renton.
This is because the sewage that leaves your home, and that leaves the homes on the hills around you, travels by gravity to the Metro treatment plant. After all, everybody knows that *ahem* “sewage” flows down hill. But if the sewage reaches still water, it will stop flowing toward the plant. And when it stops flowing toward the plant, it can turn around and start making its way toward your house.
Planners are predicting that in a worse case flood of the Green River, the Metro plant could end up being on an island, with flood waters as deep as 10 feet on some of the streets surrounding it. Unfortunately, when streets get flooded, manhole covers start admitting water into the sewer system. These covers generally deflect rain, but they are not water-tight, and when they get submerged they will not keep water out of the sewer. In fact, as the sewer gets overwhelmed by storm water, manhole covers can be completely displaced by storm water… literally lifted up by the ebb and flow of the water, and then left dislodged to admit even more water.
In some scenarios, if the streets around the Metro plant all overflowed with flood water this winter, sewage from Renton Highlands, Talbot Hill, Renton Hill, and West Hill could literally start bubbling up in the homes in the lowlands. It’s nasty, and I don’t know for sure that this would happen, but it is a distinct possibility.
Your number one…and number two :-)…defense would be a sewage back-flow preventer. This is basically just an engineered check valve, which is installed in the sewer line where it exits your home.
My son and Renton Ben are working on a website for one local company that is helping outfit homes with these valves. And I’m sure there are many other plumbers that will help you to install one if your home is at risk.
If you have a home or business in the lowlands of Renton, I strongly recommend you research this a little further and consider having one of these back-flow valves installed if you don’t already have one. A sewage backup into your home would not only be disgusting, but it would be a bio-hazard as well, and obviously leave your home uninhabitable until you got it thoroughly cleaned. Finding help getting it cleaned could be very difficult if the Green River floods, since contractors and equipment suppliers would be inundated.
The effect of sewer backup in a basement is even more dramatic. Graphic thanks to City of Regina, California
Thanks for this, I’ll link to it. Lots of people I know in river valleys.
Whadda shitty deal that is.
I have nothing constructive to add, but I LOVE the illustration. lol
What can be messier? How about Obama and the democrats actually getting their liberal agenda through? Now that’s a mess! TCC
Renton Areas Affected?
Randy,
Have you seen any worse case projections showing how much of Renton may be affected by floodwaters? I know the Elections Office on Grady Way has moved, and there are concerns about the wastewater treatment plant. How about areas closer to downtown?
Thanks.
Re: Renton Areas Affected?
The City has posted flood maps on its website: http://rentonwa.gov/government/default.aspx?id=26343
Re: Renton Areas Affected?
How about a map of the service area of the Renton Metro treatment plant?
Get out the fishing gear folks. This could be a record year for boneless brown trout running in the streets. TCC
A paranoid gun nut with the humour of a 12 year old. Renton is certainly earning its reputation today.
Go down to McLendons and pick yourself up a sense of humor. You’ll find them on isle 15. Also, don’t forget to vote yes on initiative 1033. It will pass with flying colors. TCC
A couple other challenges if things go bad:
1) Bad enough to try cleaning out a flooded house, but try then to dry it out in the middle of winter when it’s cold and raining outside. Talk about mold problems…
2) Not all sewage runs downhill – some of it is raised and/or moved along via sewer pump stations – which are powered by electricity. Much of our electricity is served by underground lines and vaults – which will be filled with water and shut down during flooding, and afterward as well until they can be dried out and lines/switch gear checked and repaired. It’s not just where is the service area for the Renton sewage treatment plant – it’s also where are the service areas for the power substations etc. that are also at risk.
“Another concern, even with a relatively small flood, is the loss of power. Puget Sound Energy officials have said the utility will shut off power if there is standing water, according to Straka and Zimmerman.” in the Oct 9 Renton Reporter
So does the Renton Sewer Plant have back-up power generators, or is our fair city set to receive all the sewage from the entire Eastside into a plant that will be out of order? Now that will be a back-up…
And when all else fails, keep one of these on hand (great for earthquakes too!):
http://www.cabelas.com/p-0009518.shtml
Great idea although by the time you need it, chance are good that it will be to late.
Here is the actual link:
http://www.cabelas.com/p-0009518.shtml
Of course, another good idea would be to fix the dam.
That is a swell idea. The Corps of Engineers would probably like to have some one bring that to their attention.
If we just had a “shovel ready” project, and if we printed a buttload of money to pay for these projects…
Yep, the timing is simply wrong to fix the dam at this time. Maybe someday.
Yeah, I suppose we could always make up for the loss of business by starting a local cranberry and rice industry
Sitting on the sidelines – it does seem like the Corps of Engineers sat on their hands for six months before they reacted. I’m not sure what the role of the Corps of Engineers, but they’re act like a lazy sole-source government contractor and nothing like an “Army.” Now, their little uncured concrete curtain is too late.
We American have become very risk averse, so much so that the risk avoidance is almost becoming more of a problem than the original risk.
We’re kinda like a fat-man that won’t job because he’s afraid of dogs, and he then dies of a heart attack.
Or something.
Renton should waive sewer backflow permits
Randy – on the radio this morning they talked about the Renton sewer plant getting ready for the flood. If it fails, there will be no sewer service “east of Lake Washington” and it will literally be a mess. We in Renton are downstream (or is it “down-sewer”) from the eastside, so the pressure at our end will not be pleasant.
Auburn has waived the sewer backflow permits – can Renton do the same?
http://www.pnwlocalnews.com/south_king/aub/news/65667237.html