MANAGEMENT OPTIONS TO SUSTAIN GROWTH WITHIN WATER-STRESSED SPRING CREEK WATERSHED, RIDGE AND VALLEY, CENTRE COUNTY, PENNSYLVANIA

The Susquehanna River Basin Commission considers the 145-mile² Spring Creek Watershed over-stressed, given 8 dominantly groundwater and 4 municipal surface-water withdrawals, excluding Penn State's University Park Campus and Rockview Penitentiary. The Commission regulates >=100,000 gpd withdrawals and encourages mitigation measures to sustain multiple water needs while avoiding significant cumulative adverse impacts to groundwater levels, base flows, water quality, wetlands, wildlife, and other living resources.

The watershed is undergoing rapid development driven by Penn State's multi-billion dollar teaching, research and outreach budget that locally serves 46,000 students as well as economic activities made accessible and beneficial by I-99 and I-80 (e.g., growing medical, public and governmental services; research and development; construction). In support of this growth, high-quality limestone and aggregate are being mined and quarried at 4 locations below the water table.

Constrained by the Commission's low-flow protection policy, six options are available to sustain growing water demands:

· Import from adjacent watersheds

· Expansion of groundwater contributing areas by shifting 3 transient groundwater divides within local Ridge and Valley Appalachian karst aquifers

· Voluntary and mandated conservation during declared droughts. (e.g., Today, Penn State’s per student water use is ~45 gpd v 95 gpd nearly 20 years ago.)

· Management of stormwater flow enhanced by interconnected impervious surfaces and diverted from evapotranspiration.

· Wastewater reuse (e.g., Penn State's Living Filter returns 100% of its effluent to crops and forests; University Area Joint Authority’s 1 mgpd beneficial reuse system).

· Regional climate change between 1895 and 2017 includes +0.137°F/decade rise in temperature and +0.267 inches/decade precipitation increase. Patterns of increases in and intensity of flood events are driven by temperature and prevailing storm tracks, likely increasing the availability of stormwater for future harvest.

Given the will, a mix of these 6 options is a way forward to sustain growth within these headwaters and is supported by a well-understood hydrogeologic framework.