Sludge and Septage

Sludge and septage, both wastewater products, are different materials:

• Sludge is the semi-solid material products by treatment processes.
• Septage is the liquid and solid material removed from septic tanks, cesspools, holding tanks, or other sewage treatment/storage units.

NHDES regulates the removal, transportation, and disposal of sludge and septage to protect the environment.

• Watch: Septic System Management for Homeowners
• What can be flushed down the toilet?

Biosolids are derived from treated wastewater sludge. These residuals are considered safe when they meet federal and state requirements for pathogen reduction and pollutant limits. Biosolids can be applied to land as a fertilizer to improve soil properties and enhance crop growth.

Visit our Managing My Waste page to learn about other types of household waste.