How phosphorus escapes from construction sites

When you see mud in the lakes, you know phosphorus is escaping. 
Lake Mendota 7/7/10.



Studies show that 19% of the phosphorus in our lakes--an important nutrient that causes the growth of toxic algae--comes from construction site erosion.

Is dumping concrete waste illegal in Madison?

Concrete wastewater, and the slurry from cutting concrete with a saw, are very toxic to aquatic life.  In addition, the waste contains chromium, a known carcinogen that can contaminate groundwater.

So... is dumping this material at a construction site illegal in Madison?

Rawson cleans mud from box culvert

Thanks to Rawson (and City inspectors) for cleaning the mud from the box culvert under Old Middleton Rd. 

Now the mud won't move to the lake in the next big storm.

Concrete wastewater pollution in Madison

After I noticed concrete wastewater dumped at many construction sites around Madison, I decided to research the topic.  Here's what I found... so far.  Research in progress--your comments are welcome.

Concrete waste illegally dumped by Rawson Contractors close to Lake Monona at Lowell St. 11/7/10

Concrete wastewater is a white or grayish fluid.  It comes from washing equipment used to mix or deliver concrete.  It is often combined with a pile of leftover concrete.  You can spot it as a white stain--on pavement,  or on a prepared surface about to be paved.

Rawson fails to clean mud from box culvert

The Rawson construction site on Old Middleton Rd is a mess--completely unprepared for rain.  In their defence, no rain was forecast for the weekend.  But much work remains to prepare for the rain forecast for next Thursday.