Mayor Daley has suggested that flooding in Chicago could have been prevented if residents put out barrels to collect rainwater running off roofs of houses. The Tribune has it that 90 Billion Gallons of storm runoff went into Lake Michigan during the weekend downpour.
With around 7 Million people in Chicago, that would be 12,857 gallons collected per Chicago resident, or 233 barrels per person (at 55 Gallons per barrel). A container holding 12,857 gallons would measure 1718 cubic feet or approximately 12ft x 12ft x 12ft…..so merely having 7 million tanks at 12×12x12 would have prevented the flood, sounds easy enough.
Steel tanks at 1/8 in thick would weigh in at 3700 pounds, so 7 million of these tanks would total approximately 25,900,000,000 pounds of steel. Steel costs approximately $630 per ton, So the Mayor is suggesting for a mere $8 Billion we could have prevented the flood, in addition to the $3 Billion already spent on the Deep Tunnel project.
Following up on the sewage in the lake, at 90 Billion gallons of runoff, and 1% raw sewage, that is 900 Million gallons of raw sewage in Lake Michigan. Wilmette has reportedly upped the amount of chlorine in the drinking water.
Those with access to calculators, please upgrade my arithmetic.
olivier says:
I would just let that Water collect in every oversized finished basement in Wilmette.
John Powers says:
Jay,
One of the nice things about comments, is that you are free to do your own math to improve mine. There are no restrictions on using a calculator so have at it.
I doubt that green roofs are going to hold billions of gallons of water for very long.
The straightforward examination is that what Chicago has done did not work.
JBP
Jay Alt says:
Thanks for the offer but the work doesn't rise to a level that merits review. I reserve my help for for more useful projects, a son and a daughter with trig & calculus homework.
The drainage programs you criticize keep sewage and cholera out of Chicago's water supply.
They are effective most of the time; the last such spill/flood was in the early 90s, iirc.
The programs are working properly. Even with this month's flood, chlorine treatment prevented contamination.
The Tunnel project began 30 years ago and like most public works projects it took decades to finish. The city could accelerate completing the 3 attached reservoirs; they will expand storage capacity 4 - 5 times. I assume the rock removed by quarrying the reservoirs is being used in road and construction projects.
If you require another pointless calculation, find the number of steel boxes to store the rock rather than putting it to good use.
Daily's suggestions for a green infrastructure are the most cost-effective way to keep storm water
out of the system.
John Powers says:
Jay,
Daley's suggestion is lunacy. No one is going to hold 233 barrels of rainwater at their home. Rain which does not reach the Mayor's speculative barrels goes right into the storm sewer or basement.
Given that 900 Million gallons of raw sewage just got poured into the water supply I fail to see how the MWRD can claim to "keep sewage and cholera out of Chicago's water supply".
The tunnel project is not working.
JBP
Citizen says:
JBP,
You cannot criticize the Deep Tunnel project in the manner you have. It has provided billions of gallons of water diversion and prevented millions of basement floodings in the past 30 years. There is no incident where we could have prevented flooding in this situation, and I think we all agree that the Mayor's comments are ridiculous. As is the Mayor himself, incidentally. And just imagine how much of that sewage overflow would have been dumped into the rivers had it NOT been for the tunnel project. Another point of contention; the Mayor does NOT control the MWRD nor have any legal power in its operations. It is an independent agency NOT linked in any way to the City of Chicago. It serves all of Cook County and some surrounding areas.
John Powers says:
OK Citizen,
It could have been worse. But the MWRD does not publish nearly enough information to prove its worth.
It is certainly possible to prevent flooding in Chicago. The MWRD has some responsibility here. There needs to be some metric as to when the sewage is dumped in the lake, and when it is dumped in your basement.
Any claim that Mayor Daley does not have clout at the MWRD is just fiction. I don't think he controls very much of anything in the City, but he certainly can influence the MWRD.
JBP
Jay Alt says:
Your view is overly simplistic and doesn't begin to touch on what Chicago has done or plans to do. (Your math is wrong too: the whole metro area has not been roofed)
- Stormwater Control Projects -
increase permeable surfaces and paving
use natural landscaping
preserve or rebuild wetlands
use natural retention basins
green roofs
downspout
rain barrels
cisterns
filter strips along parking lots
diversions and drainage swales
bioinfiltration
rain gardens