Northwestern University
OP-26: Water Use

We only have information regarding reused water going back to our FY 2013

We have four rainwater harvesting systems on campus: three cisterns and one collection field. The cisterns range in size from 120 gallons to 12,000 gallons. The collection field captures rainwater after it perks into the ground through a storm trap. The water is then stored in a 12,000 tank and can be directed out for irrigation through pumps.

All buildings have a water meter.

Recently renovated residential buildings feature low-flow showerheads, toilets, and faucets. Some buildings also have automatic faucets. In 2013, the Associated Student Government Sustainability Committee gave away free low-flow showerheads to off-campus students to help them retrofit their own bathrooms.

Our washing machines in residence halls have been upgraded to efficient, Energy Star models that load from the front, to minimize needed water.

Drought tolerant and adaptable plants are used across campus. We're also testing a low-mow lawn by Harris Hall, which only needs to be mowed once per year and requires little watering. Some areas of campus use stone instead of grass, in conjunction with very drought tolerant plant species.

The University utilizes irrigation controllers which adjust water usage. The controllers are connected remotely to a central computer which collects weather data specific to our area and applies the information to the system. An ET (evapo- transpiration) calculation is downloaded automatically on a daily basis and adjusts the irrigation output for the areas watered. We also use sun clocks and rain meters to control our irrigation based on conditions.

Install Water-saving Devices in Campus Buildings We aim to create infrastructure that reduces water waste. We’ve installed the following water-saving equipment on campus: Toilets, faucets, and showerheads fitted with low-water-flow fixtures. Toilets with dual low and high flush valves in newer buildings. We closely monitor water use across campus, and any abnormalities are quickly investigated and remedied. Irrigate Less We have installed a myriad of technologies such as solar clocks, rain gauges, and moisture sensors that calculate air moisture to determine when it will rain to avoid wasting water, time, and energy. We diligently follow the City of Evanston’s irrigation restrictions on weekdays from 10:00 am to 4:00 pm from May 15 to September 15. This restriction is in effect because plants do not absorb water efficiently, so the water evaporates and is wasted. Monitor Stormwater and Runoff Northwestern lakefill: As our campus is located on the shores of Lake Michigan, we're dedicated to doing our part to keep it clean and healthy. We focus particularly on stormwater collection and management to prevent harmful run-off. The use of synthetic fertilizer is kept to a minimum, and we frequently test soil and custom blend fertilizer that provides only the lacking nutrients. Conserving water and reducing storm runoff is another priority at Northwestern. Water is recycled in creative ways through bioswales, green roofs, and daisy basins. Bioswales are landscaping mechanisms that use terracing to naturally draw water to specific locations. Northwestern has bioswales near the athletic fields and parking lots to move water to plants that need it. Green roofs, which minimize stormwater runoff, are found at the Wild Roots Garden on the Norris University Center South Lawn and at the Ford Motor Company Engineering Design Center. Daisy basins are fixtures unique to Northwestern that divert stormwater runoff. Though most of them are underground, some older daisy basins are visible above ground near Norris University Center.