Frequently Asked Questions

What is wastewater "treatment"?

Wastewater treatment comprises of physical, chemical and biological processes that treat the wastewater before it can be safely discharged back into the environment. At the treatment plant, the wastewater passes through various stages of treatment:

  • Screenings removal of large solids that enter the plant;
  • Primary Clarification for removal of solids and organics;
  • Aeration to provide the biological organisms oxygen to consume the organic material and remove phosphorus and nitrogen;
  • Disinfection to inactivate and remove harmful pathogenic organisms in the treated wastewater.

How much wastewater and septage does the plant treat?

In 2021, the District treated approximately 1,797 million gallons (4.92 million gallons per day) of raw wastewater and 10.11 million gallons of septage. The wastewater treatment plant is designed to treat 5.7 million gallons per day of raw wastewater and can accept up to 72,000 gallons per day of septage.

Is CRPCD the only treatment plant on the Charles River?

The District is one of several plants collectively protecting the Charles River.

What causes sewer blockages?

Blockages are often caused by soil settlement, misaligned joints, tree roots, pipe collapse, grease buildup, or by placing items in your system that should not be flushed down a drain.