10 Year Storm Numbers For Those Unsure

We received an email following the meeting last night which included a number of questions concerning storm water management and city practices. One thing I was surprised that they mentioned (not seeing the meeting yet) was that both city manager and the stormwater guy couldn't give any figures or estimates as to the amount of rainfall that constitutes a 10 year storm. It doesn't really matter I guess - it just seems awkward that folks who use the language daily aren't sure what it means.

Anyway, the information isn't just sitting there with a google search - you simply find "a storm that has a 10% chance of happening in a given year". After a bit of digging, I found a nice chart on the Milwaukee Metro Sewer District site - http://v3.mmsd.com/, which stated the following:

10 year storm:

- 1 hour of rainfall totalling about 2 inches; or
- 24 hours of rainfall totalling about 3.7 inches

They have it broken down by addition time segments, including 6 hr, 12 hr, 48hr, and more.

Spending a bit more time on the Milwaukee Metro Sewer site revealed that they support the following:
- Rain Barrel program
- EPA Watersense
- Rain Garden program
- Water Quality research
- Water Quality Education and Outreach program

Ironically, this sounds like the goals and requirements set forth in the Oshkosh Comprehensive Plan that we haven't acknowledged, or worse, blatantly disregard. I'm not exactly sure how the council received resident requests for water quality improvements to be designed into the Melvin Ave watershed, but I did receive an email that Rain Barrels were a topic met with laughs. Interestingly, today Milwaukee Metro Sewer District announced the following 100 gallon challenge to its customers:

"We would like to propose a simple and elegant way that you can join us in doing our part to protect Lake Michigan: we call it the 100 Gallon Challenge. Think of it as a 40th anniversary Earth Day pledge. The challenge is for every household which reads this newsletter to reduce the amount of water that goes into the Deep Tunnel during a heavy storm session by 100 gallons. Here's how:

First, purchase a rain barrel and connect it to a downspout on your house. Rain barrels are distributed by the MMSD and can be purchased at the Urban Ecology Center or another location for $45. A properly utilized rain barrel can save 55 gallons from going into the sewer every time it rains. Second, pay attention to the weather. If rain is in the forecast, be sure your barrel is emptied (you can use the excess water to wash your car or water your garden in between rains).

Finally, if it is raining or rain is in the immediate forecast, wait to do the laundry or dishes until after the rain event is over (this website might help: http://v3.mmsd.com/StormUpdate.aspx). This simple step can save another 55 gallons of water per household from going into the sewer. Taking short showers instead of baths or flushing the toilet less during a storm can save an additional 25 gallons. We did it, and it was so simple over 100 gallons saved!"


The point - little actions with support from the city can have a big impact on effective storm water management programming and water quality improvement.

Posted in: flood,Local Government,Our City,Water