Harnessing Greywater: A Sustainable Water Conservation Solution for New England


In this comprehensive guide, we'll dive into the world of greywater systems and how they can be seamlessly integrated into home renovations and new construction projects in Rhode Island and Massachusetts. By the end of this article, you'll have a solid understanding of the value of greywater, its sources, legal considerations, benefits, and various applications, empowering you to make a positive impact on water conservation in the northeast.


The Value of Greywater

Greywater, often underestimated, is a valuable resource, especially in regions like the northeast where water conservation is increasing more important. Greywater encompasses wastewater generated from household activities such as laundry, showers, and sinks, excluding toilet water. In a state where water resources are interconnected with the environment, every drop matters. Here's why greywater is essential:

  1. Water Scarcity Awareness: While Rhode Island and Massachusetts may not suffer from severe water scarcity, it's essential to remember that all water systems are interconnected. Conserving greywater contributes to the overall health of local waterways.

  2. Outdoor Water Usage: A significant portion of residential water usage goes towards outdoor activities like irrigation. Greywater, being relatively clean, is a perfect match for landscaping, nurturing thriving gardens and lawns.


Sources of Greywater

Understanding the sources of greywater is the first step in planning an effective system. In your Rhode Island home, consider the following primary sources:

  1. Washing Machines: Washing machines are heavy greywater contributors, making them a prime candidate for reuse. Upgrading to an energy-efficient model can further enhance your conservation efforts.

  2. Showers and Baths: To estimate greywater production from showers and baths, it's crucial to know the flow rate and duration of your fixtures. This data will guide your greywater system design.

  3. Sinks: In some regions of Rhode Island, bathroom sink water qualifies as greywater, while kitchen sink water classification varies. Always exclude water contaminated with fecal matter from your greywater system.


Legal Considerations in Rhode Island

Greywater regulations can vary from state to state, and Rhode Island and Massachusetts are no exception. The biggest obstacle we've encountered in our projects is not that greywater systems are prohibited, but they are just not covered in the building codes. Laundry to Landscape systems don't require a building permit. But in more complex systems, reusing kitchen water or bathwater, requires a bit more planning. In both Rhode Island and Massachusetts's plumbing codes, kitchen and bath water is considered 'blackwater' and therefore must be designed with extra consideration from a licensed septic designer.


Benefits of Greywater Systems

Implementing a greywater system in your Rhode Island renovation or new construction project offers several notable benefits:

  1. Water Savings: Greywater systems significantly reduce water consumption, which is crucial for water conservation efforts in Rhode Island.

  2. Time Efficiency: These systems automate plant watering, saving you time and effort in maintaining your outdoor spaces.

  3. Energy Savings: By reducing water usage, greywater systems also save energy, particularly in cases where water must travel over long distances.

  4. Environmental Responsibility: Using greywater encourages eco-friendly product choices and responsible wastewater management, aligning with Rhode Island's commitment to environmental sustainability.


Greywater Applications in New England

Greywater can be harnessed in two primary ways:

  1. Outdoor Irrigation: The most common application in Rhode Island is outdoor irrigation. This method is cost-effective, straightforward, and typically requires minimal maintenance. Obtaining permits for landscaping with greywater is relatively accessible.

  2. Toilet Flushing: Greywater can also be used for toilet flushing, albeit with more complexity. This application requires filtration, disinfection, and ongoing maintenance. While permits for toilet flushing systems can be challenging to obtain, they remain a viable option in specific cases.


Quality of Greywater Products

To ensure the success of your greywater system, it's vital to use products that are safe for plants and the environment. This includes considerations for how you select your laundry detergent, soap, and other products that go down your greywater system drain:

  1. Low Salinity: Avoid products with high salt content, as they can harm Rhode Island's unique flora and soil.

  2. Boron-Free: Products should not contain boron, which can accumulate in the soil and damage local plants.

  3. Chlorine-Free: Chlorine bleach should be avoided, as it can harm soil microbes and disrupt Rhode Island's delicate ecosystems.



Harnessing greywater offers a sustainable solution to water conservation in New England. By understanding greywater's sources, legal considerations, and the importance of environmentally friendly products, you can take meaningful steps toward reducing water wastage, conserving energy, and promoting environmental responsibility.