In Oakland county, we regularly poison our basements and our lake St Clair beaches with feces because we have a combined storm and sanitary sewer system, and because our pipes are too old and small to handle the amount of storm water from our larger rain falls. Our current commissioner claims the fault is not his, but global warming, the rains are bigger now and he can’t stop that, he says. But I claim the fault is that more and more of the county is covered by asphalt, so less rain water soaks in the ground and more is expected to go through the small old pipes (I’m running for water commissioner, by the way). A proof that it’s asphalt and not rain is the following: see the following chart of toxic outfalls into the Red Run drain the last month alone. Note that the rain amounts are not exceptionally high: 0.9″ to 1.42″ of rainfall.
Toxic outfalls into lake St Clair this month. There were also two outfalls into the Rouge in this period. Clearly, these are not 100-year events.
Oakland is the fastest growing county in Michigan, and increasingly covered by asphalt. But most of the county is still served by old sewer pipes that lead to Detroit’s Waste Water Treatment plant near Zug Island. When there is a heavy rain, the increased water from the asphalt overwhelms the small pipes to Detroit and is diverted, barely treated, into Lake St Clair. On unusually bad rain days, even this does not suffice and the mixture of storm and septic water (bio-hazard poop) comes up through your floor drains and toilets. The Red Run Drain is the red line in the graphic below.
Follow the feces to see why our beeches are polluted. From our drains to the Clinton River to Lake St Clare — right upstream of our beaches and our drinking water intake. We can do a lot better.
Storm water plus septic sewage enters the Red Run, mostly via two large pipes running north-south on the east side of the county. The mix flows through a retention basin where it is spritzed with bleach, and then, via the Clinton River, enters Lake St Clair near Selfridge ANGB. The water and feces then flow south along the Michigan shore (light blue line) where it pollute our beaches. You’ll notice that they’re closed every other week it seems. Our clean water intake is near Belle Isle (the island at the bottom of the picture) just downstream from the pollution. We can do better than to dump poop into the river just upstream of the water intake. At least three solutions seem obvious.
This is our combined sewer system showing a tunnel cistern (yuk) and the current outflow into the Red Run. The only treatment in our retention basin is a spritz of bleach. We can do better.
A first solution is to have better pumps to send the sewage to Detroit. This is a sort of no-brainer. A second suggested solution, one that is more environmentally sound, is to provide small wetlands to hold rain water. These are cheap and very pleasant for the communities. They reduce the biohazard of the storm water, they reduce the amount of runoff by absorbing some in the ground, and they provide very pleasant park spaces.
And a final, key suggested improvement is to disentangle the septic from the storm sewers so our basements and beaches don’t get overwhelmed by toxic rain-water mixes whenever it rains heavily, an inch or more. Disentangling the sewer is more capital expensive and technically demanding, but it really saves money and provides benefits if done right. We would save quite a lot by not sending so much liquid waste downtown to Detroit, and that’s savings we could pass on to you. Besides, once the storm and septic sewers are separate you won’t have to worry about your floor drains back-flowing into your basement.
The above are the general approaches I favor. They are money-saving and ecologically responsible. The incumbent, I fear, has little clue in this area. He is building two big tunnel cisterns, the first along Middlebelt road. These are very costly to build and even more costly operate. They don’t clean the septic water they hold, require the water table to be lowered, and are explosion hazards if not vented very well. They can be the right technology, but not here I suspect. The people who build these projects are the same ones who fund his campaign, though. If you’d like to see a change for the better. Elect me, Elect an engineer.
Dr. Robert E. Buxbaum, March 21, 2016. Go here to volunteer or contribute. For Oakland county water quality reports, go here.