The WDNR permeable pavement technical standard 1008 and associated technical note were recently updated with minor revisions. The revised versions of the standard and technical note are posted on the DNR website: http://dnr.wi.gov/topic/stormwater/standards/postconst_standards.html
A summary of the revisions are as follows:
- In the permeable pavement technical standard, the surface clogging capacity (Section V.D.3.) was changed from 0.6 pounds per square foot to 0.06 pounds per square foot. The initial surface clogging capacity was established for use with WinSLAMM v10.0.3. However, v10.0.3 had very limited distribution and was replaced with v10.1 shortly after the technical standard was published. As a result of modifications to the permeable pavement equations in v10.1, a surface clogging capacity of 0.6 pounds per square foot does not provide results consistent with the criteria that was used to develop the technical standard. The new value (0.06 lbs/sf)) used in v10.1 was determined to provide results that are equivalent to the old value (0.6 lbs/sf) used in v10.0.3.
- In the permeable pavement technical note, the surface clogging capacity was changed from 0.6 pounds per square foot to 0.06 pounds per square foot and the modeling procedure and example were modified to reflect the changes in WinSLAMM v10.1.