Groundskeepers tap into free water on campus
Most weekdays during the growing season, the tank labeled “Free Water from the Oakland aquifer Pitt conserves” is a familiar sight on the Oakland campus. Towed on a trailer behind a pickup truck, the 300-gallon tank, with its huge coil of yellow hose, is used to water hanging baskets and flowerbeds in parts of the campus where traditional water connections don’t exist.
But where is this free water and where does it come from?
The saturated subterranean rock of the Oakland aquifer stretches roughly from Herron Hill to Schenley Park, said Dan Bain, a faculty member in geology and planetary science. Eventually its water reaches the Monongahela River or comes out in the form of seasonal springs in Panther Hollow.
Between mid-May and October, three or four days a week, Pitt groundskeepers descend to the lower level of the Sennott Square parking garage twice a day, where, in a small utility room some 20 feet below street level, they can access water from the Oakland aquifer.
Behind a locked door, water three to five feet deep rushes at the bottom of a 15-foot deep concrete well. At the push of a button, a pump draws the water up, filling the tank in a matter of minutes.
Tim Havics, an area coordinator with Facilities Management, said the system was used to remove water from the site during construction of Sennott Square. After the building was completed in 2001, Pitt sought ways to use the water. “The flow wasn’t going to stop,” he said, adding that tapping the aquifer as a source for grounds use was the obvious solution.
In addition to watering the campus gardens, the water sometimes is used by labor crews for power washing, said Richard Veitch, assistant grounds manager.
Regardless of whether there are drought conditions or torrential rains, the aquifer, which lies below the soil and rocky soil layers of the ground, isn’t affected immediately, said faculty member Bain, who has taken his groundwater geology students to the Sennott Square garage’s lower level to view the well.
While shallow water in the soil layer is affected by precipitation and drought, the aquifer below is buffered from the effects of evaporation and thirsty trees whose roots take up water from the shallower soil.
Only when the soil is completely saturated — as is common in wintertime — does water sink deep enough to pass through the underlying rocky soil layer to enter the rock layer beneath, where it fills the spaces between rock particles.
Bain said water in the aquifer could be many years old, noting that groundwater dating in Maryland recently showed that some water in an aquifer there dated back 10,000 years to the most recent glacial period.
Laura Zullo, Facilities Management’s senior manager for energy initiatives, estimated that the grounds staff draw about 55,000 gallons of water a year from the aquifer, saving the University about $900 annually — not enough to have a huge impact on the budget, but a substantial reduction in ordinary water consumption, she said.
—Kimberly K. Barlow