As Sandy Hertz walked the perimeter of a small pond in Wicomico County one recent afternoon, a deer startled and bounded into the woods.
Geese protected large eggs at the water’s edge. Frogs croaked and ribbited. And down a hill by the pond’s spillway, a tiny turtle crawled toward the tree line.
For Hertz, deputy director of the Maryland Department of Transportation’s Office of the Environment, the journey along the water’s edge was exciting – not just because of the wildlife, but also because the site recently was outfitted with state-of-the-art “smart pond” technology.
Smart ponds regulate the flow of water from stormwater management sites, reducing pollutants and curbing local flooding. The final installation of the smart pond technology was completed recently at Walmart stores in Fruitland, Aberdeen and Hagerstown. The public-private partnership that led to the project is the first of its kind involving a state transportation department in the United States and could be replicated elsewhere in the mid-Atlantic and across the country.
“These smart ponds are another innovative way we’re working to improve the communities we serve,” said MDOT Secretary Greg Slater. “We’re being responsible stewards of the environment while at the same time helping protect the infrastructure that supports our hard-working residents and businesses.”
MDOT is partnering with the Maryland Department of Environment (MDE), U.S. Environmental Protection Agency (EPA), Walmart, The Nature Conservancy and technology company Opti on the smart ponds project.
“We’re setting an example for the nation on how to combine creative forces for cleaner water and safer communities in the face of climate change and local flooding,” said Maryland Environment Secretary Ben Grumbles. “We all win when environmental and transportation agencies work together with business and conservation leaders to deliver innovative solutions.”
Developed by Opti, smart pond technology improves stormwater pond operations using sensors and software to monitor real-time conditions such as water level and storage volume. The system, especially important now as spring rains hit the state, uses internet-based forecasts to remotely operate valves that control timing and volume of water discharge. Longer retention time increases water quality by capturing more sediment and nutrients.
When rain is forecast, the system can automatically open valves to drain the pond prior to precipitation. This helps maximize storage efficiency and can reduce downstream flooding. April is Maryland Flood Awareness Month.
“Being able to optimize the capacity of these ponds ahead of storm events will help prevent or mitigate flooding on roadways and flooding concerns for the adjacent property owners,” Hertz said.
The system also can be operated manually from any internet-connected device. System data can help prioritize maintenance needs.
“As a mission driven organization, we take great pride in delivering this innovative and highly impactful project for the citizens of Maryland,” said David Rubinstein, Opti’s CEO. “The technology we put in place is helping to protect the Chesapeake Bay and its watershed. None of this would have been possible without the excellent collaboration of the public and private sector teams. Together, we proved that we can improve environmental outcomes, greatly leverage taxpayer dollars and continually adapt to constantly changing weather patterns.”
The Walmart sites that received smart pond technology through the partnership are:
- Walmart Supercenter Fruitland, 409 N. Fruitland Blvd., Fruitland;
- Walmart Supercenter Aberdeen, 645 S Philadelphia Blvd, Aberdeen; and
- Sam’s Club Hagerstown, 1700 Wesel Blvd., Hagerstown.
“As part of the community, Walmart is honored to be part of the solution to improve Chesapeake Bay water quality through this partnership,” said Toni McCrory, Senior Director, Environmental, Health, and Safety Compliance, Walmart Inc. “The completion of these projects reinforces our goal of becoming a regenerative company by helping to protect and restore nature. Enhancing our existing stormwater assets under this program allows us to work smarter by helping to remove pollution, restore natural hydrology, and reduce flooding in a cost effective and sustainable manner. We appreciate our partners who helped make this possible.”
The smart ponds project complements other initiatives to plan, design and implement water quality improvement strategies to meet the EPA’s Chesapeake Bay Total Maximum Daily Load (TMDL) requirements for the year 2025. According to EPA, there are 65,000 privately held stormwater management ponds in the Chesapeake Bay watershed, including 18,500 in Maryland.
“It’s encouraging to see Maryland’s progress on this public-private smart ponds project that plays an important role in addressing stormwater runoff in the Chesapeake Bay watershed,” said EPA Mid-Atlantic Acting Regional Administrator Diana Esher. “Controlling stormwater runoff can result in environmental benefits across the country, and this partnership approach can serve as model for communities nationwide.”
A contract between Maryland Environmental Service (MES) and The Nature Conservancy/Opti to retrofit the three Walmart ponds as smart ponds was finalized on July 8, 2020. MDOT’s payment of $3.25 million will purchase 80 acres worth of Chesapeake Bay impervious area treatment credits generated by the smart ponds at Walmart. After MES certification of the credits, MDOT will begin purchasing the credits this spring.
“The completion of the installation of the Continuous Monitoring and Adaptive Control (CMAC) stormwater management ponds at the Walmart sites is an exciting advancement in stormwater control and pollutant removal,” said Maryland Environmental Service Director Dr. Charles Glass, P.E. “The technology saves money and improves the quality of the water being reintroduced into the Chesapeake Bay. MES is proud to be have provided unique procurement and certification processes for the project and looks forward to developing more uses of ‘smart pond’ technology.”
The technology installation at the three Walmart locations was completed between July 2020 and March 2021. As the MDOT State Highway Administration has already met MDE’s compliance goals of treating stormwater runoff from 4,621 acres of impervious area by the October 2020 deadline, these credits will be used for TMDL pollution goals among MDOT’s other agencies.
The smart pond partnership represents the first time a state department of transportation is purchasing credits from a Water Quality Trading Program. MDE established Maryland’s program, creating a water quality marketplace for credits generated by pollutant reductions elsewhere in Maryland’s portion of the Chesapeake Bay watershed. This market-based approach offers economic incentives for pollutant reductions.
The cost to MDOT for these new credits is about $37,500 per acre, including installation of smart pond technology and 20 years of monitoring, inspecting, operating and maintaining the ponds by The Nature Conservancy/Opti. That’s significantly less than the average construction cost of $150,000 per impervious acre treated through stormwater devices such as swales, bioretention cells and stormwater ponds – and that $150,000 cost does not include operation and maintenance. MDOT owns about 800 ponds that could benefit from the smart pond technology.
“We need innovative partnerships just like this one to reach a clean, healthy Bay,” said Mark Bryer, Chesapeake Bay program director for The Nature Conservancy. “The Nature Conservancy looks forward to helping build from this terrific pilot to new sites across the Chesapeake watershed and the country.”
Smart ponds are among numerous strategies MDOT has implemented to support protection and restoration of the Chesapeake Bay watershed. They complement initiatives including on-site solar panel installation at MDOT facilities, reuse of dredged sediment to rebuild wildlife habitats, tree planting, educational programing, partnerships with other state agencies and a host of other initiatives to help protect Maryland’s historic, natural and cultural resources.