Storm flooding differs from a pipe leak because river and runoff water carry silt, debris and sewage. The 2022 Hazard Mitigation Plan names the Nashua River and the Still River as flood zones, and the town's zoning restricts building in the Floodplain District shown on the Flood Insurance Rate Map.
How the crew clears and cleans
Pumps lower the water, then the crew shovels out silt, removes soaked carpet and drywall and washes the hard surfaces. Floodwater is treated as Category 3, so surfaces get an antimicrobial treatment and porous materials do not return. Drying starts only after the cleaning, because wet contaminated materials cannot dry clean.
- Pumping starts at the lowest point in stages
- Silt and debris are shoveled out before washing
- Porous materials that sat in floodwater are discarded
- Surfaces get cleaned and then treated before drying



