Title 5 Factsheet

The Problem: Nutrient Pollution from Septic Tanks on Cape Cod

Most homes on Cape Cod–more than 85%–use septic systems to treat their wastewater. While these are effective at protecting our health by removing pathogens, they are not designed to remove pollutants that endanger our coastal areas, ponds, and streams.

Septic systems allow nutrient pollutants such as nitrogen and phosphorus to escape into the environment. Once wastewater leaves a septic system, this water and these pollutants within it move quickly through Cape Cod’s sandy soils.

With so many homes using septic, the impact of this pollution is significant. Impacts include harmful algae blooms in ponds, thick muck at the bottom of bays, degradation of seagrass beds, declining shellfish harvests, and more. All of this leads to poor water quality and beach closures, which affect our tourism-based economy, recreation, our fisheries, our property values, and our way of life.

Some towns have areas of environmental concern that are particularly sensitive to pollution from septic systems. These areas are referred to as designated nitrogen-sensitive natural resource areas or NRAs.

For many towns, sewering would be an effective solution to nutrient pollution. And while most towns have included sewering in their long-term wastewater plans, it will take years to implement. Our ecosystem needs a more immediate solution.

When Title 5 is Not Enough: The Solution from a Regulatory Standpoint

‘Title 5’ refers to the environmental code that regulates septic systems on Cape Cod. When Title 5 was implemented in 1995, the primary goal was to require the installation of septic systems to minimize public health risks. The unforeseen result was that septic systems did not protect the environment from nutrient pollution, which degraded Cape Cod’s waters.

On July 7th, 2023, changes were made to Title 5 (310 CMR 15.000) to better protect our waterbodies.

What does this mean? Well, like all things regulatory, it’s complicated. Here’s what it boils down to:

As towns implement these regulations, they have two choices for reducing to Nitrogen pollution:

  • Towns can apply for a watershed permit, which would allow them to develop and implement a plan to reduce nitrogen pollution using various technologies and practices over 20 years.
  • Towns can allow a mandatory septic upgrade to be imposed on homeowners in NRAs. All homes within an NRA would be required to replace existing septic systems with Innovative/Alternative (I/A) septic systems within 5 years. These onsite systems are upgraded versions of a standard septic system. They are specifically designed to remove nitrogen.