We reached our destination - the new development of Southbridge, which on a clear day boasts one of the longest views of the capitol. Like any construction site it was a work in progress. Several other fences had been improperly installed. According to the Wisconsin Department of Natural Resources, the average acre under construction delivers 30 tons of topsoil a year downstream. If you're near a storm sewer, you're in an environmentally sensitive zone as far as the soil engineers are concerned.
Rain is where the problem begins.
The average raindrop acts like a little bomb, hitting the soil at around 20 miles per hour. Wind gusts and larger drops increase that speed. On undisturbed ground the leaves of grass and other plants act as shock absorbers, but when rain bombs fall on bare ground, they displace soil particles and destroy soil structure. As the rain continues, displaced particles move about, clogging larger soil pores that normally help absorb water. If it keeps raining, the water begins to pond, then to flow downhill - carrying displaced soil particles and dislodging more.