Wastewater Flow Monitoring

For more than 50 years, the Powdermill Nature Reserve has been dedicated to a mission of research, education, and preservation. This is accomplished through a wide variety of educational programs offered at the Florence Lockhart Nimick Nature Center.

Scientists monitor and study changes in the reserve’s local ecology and wildlife populations. The site has served as a refuge for many plants and animals, which, as a result of habitat destruction, are becoming increasingly rare in the region.

Ground was broken in 2006 to expand the center and its educational value through a $3.5 million Sustainable Facilities Development Project. The expansion is designed to provide an educational opportunity for visitors to understand green construction and how it can benefit construction projects. One component of the expansion is a “Marsh Machine” that processes all wastewater at the center.

The “Marsh Machine”

In Powdermill’s Marsh Machine, wastewater first passes through an anaerobic digester, similar to a septic tank. Next, it runs through a series of three tanks, each filled with plants that take up nitrates, phosphates, and potassium. Water then cycles through a second marsh before moving to a holding tank. The processed water is recycled to the restrooms for flushing toilets, and any excess water is pumped into a Department of Environmental Protection-approved drainage field.

The Powdermill staff was interested in monitoring water flow through the various processes of the Marsh Machine. NexSens Technology provided the data logging equipment and software to meet the monitoring requirements. Paddlewheel insertion sensors from GF Signet were chosen to directly measure flow in the pipes, sending the data via a 4-20mA signal to a NexSens iSIC data logger.

At three strategically selected points in the recycling process, flow sensors were installed using PVC and iron pipe fittings. Local displays were set up nearby to provide a local readout of total flow passing through the pipes. Data from each display is sent to a NexSens iSIC data logger connected to a PC running iChart software. Here, staff members have the opportunity to generate a graphical display with real-time flow readouts to demonstrate the value of the Marsh Machine.

Educational exhibits are also set up to test and monitor the relative health of the water as it passes through the system. At various locations, sample valves allow visitors to test the water for nitrate, phosphate, and potassium levels. Additionally, processed water flows into a trout aquarium in the exhibit hall to show visitors that the recycled product is capable of sustaining aquatic life.