Stormwater Mapping

Portsmouth DPW maintains a library of thousands of paper maps, dating back to 1809. Some detail water pipes that are still in place and in daily use.  

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The City's CAD mapping in 1994 identified infrastructure in some detail; but now the City uses GIS (Geographic Information System) mapping to detail City streets, infrastructure within the City's jurisdiction, including pipes, manholes and catch basins and to track data, such as outfalls, required by the MS4 permit.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

During the 2019 season, DPW interns collected data on the City's outfalls, and conducted dry-day field tests to sample outfalls for nitrogen, chloride and bacteria, as required.