Article courtesy of Jocelyn N. Apodaca | June 12, 2015 | Las Cruces News | Shared as educational material
Each year, according to the National Weather Service Forecast Office, monsoon season affects the Southwest between June 15 and Sept. 30. With record levels of rainfall throughout Texas, New Mexicans are keeping an eye on the Doppler radar.
New Mexico State University has its own Storm Water Management Program, mandated by law and monitored by the Environmental Protection Agency. Jack Kirby, the assistant director of NMSU’s Environmental Health and Safety Office, runs the program.
“Public entities above a certain population are required to have a water management program. The city has a storm water management program, NMSU has a program, Doña Ana County has a program,” Kirby said. “It’s EPA’s approach to containing nonpoint source pollution.”
Parking lots are a host for nonpoint source pollution. When it rains, storm water acts as a universal sweeping mechanism across the drainage area, bringing with it many of the chemicals and debris that may be in the parking lot.
The program contains six components: public outreach and education, public involvement and participation, illicit discharge detection and elimination, construction site storm water runoff control, post-construction storm water management, and pollution prevention.
A successful storm water management program strives to mimic pre-development conditions of the developed area. For instance, if the NMSU campus did not exist, the land it sits on is a sloping desert area, and while there would be runoff, there would also be a lot of infiltration. NMSU is set up to manage the runoff naturally.
“Mostly what you see – some are subtle, and some aren’t – are sloped swales. They route the storm water runoff, maybe around the building into another area to run it down the hill. These swales are there to slow that velocity to help the water sink into the ground,” Kirby said. “Or, it could be a desert landscaping area that has a small curb cut that allows water to soak into a desert feature and temporarily pond, then soak into the ground.”
The primary contributor to storm water runoff from a volume standpoint around a building is a roof. Many structures on campus aid in diverting water to gullies and ponding areas, where it will eventually be absorbed, or managed via the storm sewer system, while others use gutters and pipes to direct runoff into landscape features for infiltration.
“Managing that is where smart design comes in,” Kirby said.” If a building has eight or 10 downspouts, they can flow a large volume of water. You can shoot it out into the street, and now you have a river running down the street, or you can design your landscaping to contain it.”
One of NMSU’s best buildings highlighting the Storm Water Management Program is the Center for the Arts. It was designed to contain a 100-year, 24-hour storm event, a significant amount of rainfall.
“The way the Center for the Arts contains a storm of that size is the roof drains are routed to an underground cistern system, which I believe is about a 50,000-gallon volume,” Kirby said. “There is porous pavement in one portion of the building site, and there is a small detention pond area. All of these features control that water, allow it to slowly infiltrate back into the ground and become groundwater, without creating runoff.”
One of the lowest points on campus, Sam Steel Regional pond, on the corner of Sam Steel Way and Union Avenue, usually collects a majority of main campuses runoff, while the remainder ends up in the City of Las Cruces storm sewer system.
“A portion of our water goes to the city system, but probably about 70 percent goes to that pond,” Kirby said. “From Sam Steel Pond, there’s an outlet that takes that water to a drain, which ultimately goes to the Rio Grande. The onus is on NMSU to deliver high-quality water. Water that flows onto our campus, we’ll check that, too, to make sure there’s no contamination, taking occasional samples in times of runoff. And, I would hope and I do know that folks down the stream from us do the same. That’s how permit holders ensure that they’re not making the situation worse, nor are they receiving contamination from their upstream neighbors.”
Being mindful of the campus grounds and adopting good housekeeping practices can help keep the university’s system flowing naturally and successfully.
“Your personal habits – we have residences on this campus. Changing their oil, pet waste, fertilizing your lawn – all of these can contribute to run off. Good housekeeping practices can help. The easiest and most important is to contact Facilities and Services to report it. Common sense goes a long way,” Kirby said. “If something doesn’t look right, whether it’s the quality of the storm water, some contamination question you may have, or a volume concern you may have. Call us, and then we can address the issue.”