Sustainable Synergies: Water reclamation strategy becomes reality

Alfred I. duPont believed “It is the duty of everyone in the world to do what is in his power to alleviate human suffering.” The charitable trust established through his will became the Nemours Foundation, an internationally recognized children’s health system that owns and operates the Alfred I. duPont Hospital for Children in Wilmington, Delaware and the Nemours Children’s Hospital in Orlando, Florida, along with major pediatric specialty clinics in Delaware, Florida, Pennsylvania and New Jersey. His philosophy was one of kindness, fairness and responsibility.

duPont’s will also stipulated that his Nemours Mansion & Gardens be preserved and improved upon for the pleasure of the viewing public. Designed by architects Carrere and Hastings, and completed in 1910, the Mansion & Gardens pay homage to duPont’s French family heritage. Set amid 222 acres with 47,000 square feet of floor space, it is one of the grandest houses constructed in Delaware; with its massive ornamental gardens, it is considered to be the largest formal French garden in North America.

In 1940, nearly five years after his death, the Alfred I. duPont Institute was constructed on the grounds of the Mansion & Gardens to serve children with orthopedic and physical rehabilitative needs. Since then the Alfred I. duPont Hospital for Children has grown to be one of the nation’s most highly regarded full-service children’s hospitals.

Over the years, the coexistence of these two renowned institutions — the Mansion & Gardens and the duPont Hospital for Children — resulted in opportunities for synergy, especially in the area of sustainable systems and infrastructure. One particular opportunity existed in the area of water reclamation and irrigation. The Mansion & Gardens require as much as 40,000 gallons a day in its most demanding month, July, to support the garden irrigation and aesthetic needs of the various pools and fountains. This adds up to millions of gallons a year being purchased directly from the city of Wilmington. And yet, at the same time this water is being purchased for irrigation, rainwater runoff from the hospital grounds flows as runoff into the Brandywine Creek.

During a massive restoration of the Mansion & Gardens with phase one completed in 2008, Executive Director Grace Gary, with design input from Rodney Robinson Landscape Architects, Inc., developed a strategy for capturing, storing and reusing water runoff from the hospital grounds. However, it was not until the hospital embarked on a $256-million expansion project in 2011 that the infrastructure necessary to execute this water reclamation strategy could become a reality.

Built for families, by families

This 450,000-square-foot expansion was built for families, by families and features large, single-patient rooms, a new and expanded emergency department, family centered services and amenities, a healing garden and efficiently designed “neighborhoods” of rooms that reduce noise and provide a more efficient clinical care environment. A five-story, light-filled, multi-purpose atrium entrance is accessible from the 188-space underground parking garage. A rooftop helipad with direct access to critical care and operating rooms improves care for the sickest children.

With the goal of becoming LEED Silver certified, it made sense to incorporate sustainable elements wherever possible. Key guidelines recommended measures for conserving natural resources, such as water, and reducing impacts on developed and undeveloped land. And considering the original estate was fully self-sufficient with orchards, vegetable gardens, a dairy herd, beef cattle, greenhouses and even a backup power plant, further integrating the hospital and mansion in this way is a fitting tribute to the legacy of Alfred I. duPont.

Nature aids process

The plan called for installing three cisterns on the hospital grounds. When the system is complete, some mechanical filtering will occur in the cisterns and then the water will be pumped into two above-ground bio-retention pools that can hold a combined 100,000 gallons. There, a natural system using plants will filter and remove heavy metals and some materials from the water. It will actually be cleaner when released than when part of a rainstorm. The system will help recharge the immediate aquifier and integrate modern sustainable technology with the integrity and beauty of the landscape.

“By harvesting rainwater runoff from the Nemours Hospital parking lots and roofs, the Mansion & Gardens will be able to use these onsite water resources to help reduce their dependence on the municipal water supply and provide alternative green solutions for managing stormwater throughout the grounds,” says Geoff Anderson, associate, LEED AP, with Rodney Robinson Landscape Architects, Inc.

The reality is all the water cannot be stored, so the plan for this project is to store to capacity and use. Also, it must be cleaned before being used to irrigate the lush grounds — think of the salt, oil and other detritus on macadam.

Designed so the grounds will have water to use during the driest month, a retention and reclamation zone is being installed. This is a sophisticated system but simple in its execution. It will enable the estate to purchase less water and optimize operational and maintenance practices. The cisterns are in place, and construction of the bio-retention pools is pending county approval. Construction on this next phase of the project is expected to occur after the first patients occupy the hospital expansion in October. An additional bio-filtration system is being planned that will further connect the reclamation project to existing water bodies within the gardens.

Dr. Robert Lyons, professor emeritus and former director of Longwood Graduate Program at the University of Delaware, says it well, “This is a great way to have a Delaware icon, our children’s hospital, combine emerging green technology with its landscape; think of it as ‘green maintenance,’ and it speaks well for a sustainable future.”