Water Reuse Case Study: Brooklyn, NY

The Domino District Non-Potable Water Reuse Project will be constructed as part of an effort to revitalize the historic Domino Factory in Brooklyn, NYC, NY. The redevelopment project will include 600,000 square feet of office space and 3,000 apartments, 700 of which are subsidized for low- and middle-income tenants. 

The planned district-scale non-potable water reuse system will function as follows:

1. Wastewater is collected from 5 newly constructed buildings, servicing over 8,000 people, with a capacity of up to 400,000  gallons per day (approximately 1,500,000 liters per day);
2. Wastewater is treated using an innovative treatment process that use only 10,000 square feet of low value below ground space. The treatment processes remove trash and fine particles, filter and purify the water using a membrane bioreactor, and disinfect the water with ultraviolet light and ozone; then
3. High quality recycled water is pumped back to 3 of the buildings through purple pipe lines for non-potable use (e.g., toilet flushing, cooling tower makeup, and irrigation). Excess treated wastewater is discharged directly into the East River.

The reuse system will reduce potable water use by using recycled water for non-potable uses. The reuse system will also reduce the discharge of untreated wastewater into NYC’s combined sewer system. The decreased burden on the combined sewer system can prevent untreated wastewater from flowing into local waterways through CSOs.
Other aspects of the redevelopment project will lower stormwater flows to NYC’s sewer system which can help reduce the frequency of CSOs. For example, through an innovative private-public partnership, the project integrates green infrastructure and public park space which absorbs a portion of the stormwater generated onsite. Although the project does not treat or reuse the stormwater, the use of green infrastructure lowers the flow of water into the area’s sewers. This space also enhances public access to the waterfront.

Benefits

Some of the benefits associated with this district-scale water reuse project include:

• Reduces potable water use (up to 200,00 gpd or approximately 750,000 liters per day);
• Provides a drought resilient water supply to the buildings for non-potable uses;
• Lowers use of existing wastewater infrastructure capacity through the reduction of flows to the sewer system and wastewater facilities;
• Reduces incidence of CSOs by incorporating green infrastructure;
• Provides property owners with cost incentives through the Water Conservation and Reuse Grant Program.

Policy, Institutional, and Regulatory Environment

The New York City Construction Codes regulate permitted onsite water reuse systems that utilize four sources of water: rainwater, stormwater, gray water, and blackwater (sewage). The level of treatment required depends upon the water source and the end uses for the treated water (i.e., rainwater will usually require less treatment than wastewater).

DEP has coordinated closely with the New York City Department of Buildings (DOB) and Department of Health and Mental Hygiene (DOHMH) to provide more clarity on the codes and plumbing requirements needed to safely treat and reuse wastewater in this project. DEP is currently working with DOHMH to develop new standards that follow the recommendations of the National Blue Ribbon Commission for onsite non-potable water systems, of which DEP and DOHMH have been active participants.

Given the innovative nature of the Domino District Non-Potable Water Reuse Project, additional permitting steps needed to be taken. For example, additional permitting was required to connect sewers across multiple lots within the project site which essentially removed the 11-acre (approximately 4.5-hectare) project site from discharging to the existing sewer system network. By taking this step, the project will prevent the flow of wastewater into the existing sewer network under most operating conditions.

The project is designed to treat more wastewater than needed for allowable end uses onsite. To address this, the project team has had discussions with the New York State Department of Environmental Conservation (NYSDEC) to receive a State Pollutant Discharge Elimination System (SPDES) permit to allow for the release of excess treated wastewater via an existing outfall to the East River.  This discussion is ongoing and currently pending final permit issuance by NYSDEC.

The developer of the project was incentivized to construct the reuse project because of:

1. Corporate responsibility – there was a desire for an environmentally responsible project that benefits the larger community.
2. Site-specific opportunity – the location of the development opportunity along the river with multiple continuous lots made onsite treatment, reuse, and safe discharge of treated wastewater possible.
3. Project scale and ownership model – multiple lots are owned by the same entity who has a long term ownership interest. The project scale also allowed for the adoption of a larger scale reuse project which was more economically feasible.
4. Financial incentives - grant and rate discounts added up to a return on investment that worked for a long term owner. As long-term property owners, the developer’s investment in community amenities may not have immediate financial returns, but add to the vitality and sustainability of the neighborhood over time.

Financial and Contractual Agreements

Several funding sources were used to offset the cost of the $16 million reuse project for the project developer. For example, DEP funded a portion of the capital costs ($4 million) associated with constructing the project through the Water Conservation and Reuse Grant Program. The Water Conservation and Reuse Grant Program provides commercial, industrial, and multi-family residential property owners with incentives to install fixture retrofits and other water efficiency technologies, such as onsite water reuse systems, totaling $50,000 or more on a single private property.

DEP also offers a 25 percent water fee discount to customers who install water reuse systems that reduce potable water demand by at least 25 percent as compared to other non-participating properties of a similar size and use. A 75 percent wastewater fee discount is also offered for properties that discharge less than 25 percent of their total annual wastewater flow to the city’s sewer system. DEP recently revised its rate structure to allow district-scale reuse systems, such as the Domino District Non-Potable Water Reuse Project, to apply for these significant cost incentives.

Lessons Learned and Conclusions

One of the most critical steps for the implementation of water reuse systems is developing appropriate government oversight and controls. DEP successfully coordinated with DOB and DOHMH to navigate and adapt regulations for water reuse in New York City.  The project team also needed to align the unusual elements of the district-scale reuse system with regulatory and critical infrastructure objectives and demonstrate that it is cost-effective and competitive with traditional approaches. Cost and the availability of space are important factors for most developers when considering building district-scale reuse projects. Stronger public-private partnerships are needed to improve the economic viability of these projects. Better public-private partnerships also have the potential to improve regulatory and funding mechanisms which would make project implementation smoother. Innovative thinking, collaboration and perseverance has been critical between the developer and many levels of government to make the Domino District-scale reuse project a reality.

Background Documents

• New York City Department of Environmental Protection. 2023. Water Conservation & Reuse Grants.
• New York City Department of Environmental Protection. 2023. Combined Sewer Overflows. 
• New York City Department of Environmental Protection. 2022. 14 Wastewater Resource Recovery Facilities’ SPDES Permits Combined Sewer Overflows Best Management Practices Annual Report. 
• New York City Department of Environmental Protection. 2018. One Water NYC: 2018 Water Demand Management Plan. 
• WateReuse Association. 2021. Access to Safe and Affordable Water: The Case for Investment in Water Reuse.