Porous Pavement Alleys

The City has two alleys located near flood prone areas in the downtown area.  Both alleys are located within three blocks or the Straight River, a water body listed on the 303(d) list for both turbidity and fecal coliform impairments.  The native soil located in this area is sand, which provides for increased infiltration.

The City will study of different reconstruction and repaving approaches for these three alleys:.

  1. standard imperious paving
  2. porous concrete, and
  3. porous asphalt.

The alleys are very close together and will have identical rainfall events. The City will monitor stormwater runoff from the three alleys over a three-year period. In addition to the stormwater benefits of the two porous alley treatments, this portion of the Project will generate valuable paired-watershed data about the performance of these three paving options.

 The information and reporting from this work will include:

  1. construction cost data
  2. installation experience & constructability
  3. visual inspection reports
  4. 3-year monitoring of stormwater flows
  5. long-term maintenance costs & variations
  6. experience cleaning of porous pavements with City street sweepers.

This information will provide valuable comparison data for the State and provide a stormwater application for City officials and citizens to observe and evaluate. The positive benefits of the porous paving to stormwater flows will provide neighborhood flood control and water quality improvements for the Straight River.

Porous Pavement at Work