Moorhead Environmental Complex

The LEED Platinum Moorhead Environmental Complex at the Stroud Water Research Center in Avondale, Pennsylvania, treats and uses water in a way that closely mimics nature. Its design helps protect nearby White Clay Creek, a National Wild and Scenic River, and acts as a teaching vehicle and a model for others to follow. “[Stroud director] Bern Sweeney was the main driver of this whole thing,” says Tom Nason, CEO of Nason Construction. “He had a vision for a sustainable building to go with his mission of fresh water stewardship, and that’s really what drove us.” Detailed below are the finer intricacies of the project that so elegantly exemplifies its mission.

Managing Storm Water

Because the complex is in a rural area with no connection to city water and sewer systems, it needs to supply and manage its own water, and it begins on the roof of the building. A 14- by 30-foot green roof, planted with 12 species chosen for their drought-resistant qualities, absorbs water. The water that falls on the rest of the metal roof is routed into a 6,000-gallon cistern buried in the ground, which is used for flushing toilets and in environmental chemistry labs.

Situated in front of the Moorhead Environmental Complex, the rain garden retention basin uses native plants to reduce downstream flooding and filter runoff pollution, protecting nearby rivers and streams. Rain gardens also help recharge local groundwater and improve water quality and provide habitat for birds, butterflies, and beneficial insects that eliminate pest insects and suppress mosquito breeding.

Rain Gardens

Keeping with the Moorhead complex’s mission, the team designed an integrated landscape system that manages water like the native forest. Rainwater flows off the landscape into connected rain gardens, semi-natural depressions planted with native plants located throughout the complex that allow water to infiltrate into the ground instead of running off into the nearby creek. Parking lot water is routed into an underground infiltration trench, and excess water flows to surface rain gardens at a lower elevation and then, if necessary, through level spreaders into forested wetlands. Finally, walkways made with pervious pavers are laid on a thick bed of gravel for additional water storage and infiltration.

Solely Geothermal

The center installed its first geothermal wells in 1996. With the construction of the new building, it added eighteen 450-foot-deep wells to the existing 28 wells (each 300 feet deep). In the process, the team installed a new in-ground, closed-loop system filled with propylene glycol and tied the new system into the older one. “The new building is one-hundred percent heated and cooled by geothermal, so the only utility bills we receive are electricity bills, which run pumps, fans, and compressors associated with the HVAC units,” says Stroud vice president Dave Arscott, who adds that the new system also improved the heating and cooling performance of older buildings.

Restroom Reductions

The complex has two types of toilets. Two Clivus Multrum waterless composting toilets are connected to the education classroom with liquid waste flowing into storage tanks that eventually route waste into the complex’s wetland wastewater treatment system. More than 90 percent of solid waste is converted to water and carbon dioxide with a high-carbon bulking material, such as bark mulch or sawdust, and redworms. The process leaves a small amount of dry material similar to topsoil that is removed by a licensed handler. Four other staff toilets are flushed using water from the rooftop rainwater system with electronics automatically switching to the groundwater system when the rainwater cistern is empty.

Wetland Wastewater

The complex received a $239,000 grant from the Pennsylvania Department of Environmental Protection to help construct a wetland wastewater treatment system, which is one of the first of its kind in Pennsylvania. “While it may appear to be a handsome planting bed, it is actually a serious piece of bioengineering,” explains M2 Architecture’s Muscoe Martin. All effluence is routed to a septic tank, which holds solids and passes liquids through a wetland designed to remove excess nitrogen and carbon compounds, a vital step given the complex’s location adjacent to a protected National Wild and Scenic River. Also minimizing the wastewater’s impact, the water is injected into the ground via a drip-irrigation field, which is less invasive to construct than a traditional drain field.