Where Does Our Water Come From?

Pace student and PLV Campus Outreach Intern for the .007% Campaign Khari Linton goes knee-deep in water to explain where it comes from and where it goes after we use it.

Khari Linton

At an early age, I wondered where our water came from. I used to think it came from the ocean through pipes that led the water directly into our homes. As a child, I traveled to Marco Island, Florida with my family every summer. I remember one day in particular, when we went to the beach and saw sewer pipes that emptied into the ocean. At first glance, it did not look like much more than simply two black pipes that went far out into the water. As I got closer, I could smell the garbage and see the weirdest looking insects hovering around the pipes. And yet, the water was clear blue with white sand. So then I thought: “Water must come from the ocean, then we use it, and then it goes into the drain and into other pipes that go deep into the ocean so it will have no effect on us.” I’ve obviously come to understand that that is not exactly how it works. For many New Yorkers who do not have a clue how a water system works, ours is quite a marvel. Here is an overview of what happens before water reaches our taps and after it flows down the drain on the Pace Pleasantville Campus.The Pace University-Pleasantville water supply comes from the Catskill Aqueduct. An aqueduct is a structure built to carry a large quantity of flowing water, usually to a populated region. At the time it was being built, the Catskill Aqueduct was compared to such great man-made constructions as the Panama Canal. Water flows throughout the system at a rate of about 4 feet per second or about 550 million gallons per day. The 163-mile aqueduct starts in the Catskill Mountains at the Ashokan Reservoir in Olivebridge, Ulster County. It travels south towards Orange County, and then crosses underneath the Hudson River to Putnam County. The system crosses the Hudson River using an inverted siphon, a pipe that is formed into a U-shape, which causes the water to flow downstream by the pull of gravity. The aqueduct then enters Westchester County and flows to the Kensico Reservoir in Valhalla and, when it is not stopping at Pace, continues on to the Hillview Reservoir in Yonkers. The Hillview reservoir feeds two tunnels that lead to New York City. While many microbes die naturally during the long trip, the water is treated with chlorine to kill organisms, fluoride to prevent tooth decay, sodium hydroxide to raise pH levels, and orthophosphate to prevent lead from leaching into the drinking water. These necessary chemicals are added the Croton Lake Gate House in the New Croton aqueduct, Kensico reservoir, Hillview downtake chambers, and the Jerome Park Reservoir gate houses.

Pace Pleasantville purchases our water from the Town of Mount Pleasant, which purchases its water from the Town of Newcastle Water District, whose primary source is the Catskill Aqueduct system. The secondary source is the Croton Aqueduct system. The water purchased by Pace originates from a surface source (e.g., river, reservoir). Surface water is naturally replenished by precipitation and naturally lost through evaporation. According to the EPA, Pace University-Pleasantville’s current water system serves 2,753 consumers with 29 service connections at both Briarcliff and Pleasantville campuses.

As you now know, water takes quite a long journey to reach us. Now, you must be wondering where it all goes once it is used. ‘Raw sewage’ travels through a building’s pipes until it reaches local sewers that are owned and operated by town sewer departments. Sanitary sewers are underground carriage system specifically for transporting sewage from houses and commercial buildings to treatment plants. Raw sewage generated at Pace travels by gravity in inverted siphon pipes down to the Yonkers Wastewater Treatment Plant (WWTP). That’s right: when you flush the toilet in Miller or use the shower in your dorm, you are sending that water all the way down to Yonkers. These water treatment systems were created to eliminate the waterborne diseases that became so abundant in the late 1800s and early 1900s and to supply a growing population that demanded clean water to use for everyday needs. The plants were not only made to maintain water quality, but to improve that quality and protect the health of citizens.

The WWTP mainly uses processes such as primary and secondary treatments to remove contaminants from wastewater and household sewage. Primary treatment slows the flow of the water to allow heavier solids to settle to the bottom of the holding tank and lighter materials float to the top. The lighter materials are skimmed from the top of the surface and the settled solids (activated sludge) are collected in a hopper towards the base of the tank where it is pumped to sludge treatment facilities. The collected sludge contains potentially beneficial fertilizers for plants. The organic carbon in the sludge, once stabilized, is also desirable as a soil conditioner, because it improves soil structure for plant roots. Then the water flows to secondary treatment which degrades the biological content of the sewage derived from human waste, food waste, and soaps. Once the wastewater has gone through these processes, it then flows into the Hudson River with a small addition of chlorine. 300 million gallons per day flow into the Hudson River from the Yonkers WWTP.

The systems that bring and take water to us are incredible icons of human engineering and it is a wonder why we do not appreciate them more. Most of us do not even know anything about them. Even though these systems operate below capacity, it does not mean our use is sustainable. If we continue to introduce more water conservative measures and revolutionize wastewater treatment to handle our growing world populations, we can ensure the future of our most precious natural resource.

Written by Pace student Khari Linton

Have you been keeping up with Pace Academy’s .007% Campaign? For the 2012-2013 academic year, the Pace Academy for Applied Environmental Studies, with support from the GreenPace Sustainability Committee, has set out to create greater awareness of water issues through the .007% Campaign. From water-inspired photography projects and film screenings, to fundraising events and a mock hearing on the Clean Water Act, the .007% Campaign is preparing to flood Pace University. Each month in the Pulse, you’ll also find a blue graphic with a number indicating a fact about water that may surprise you.  Get involved in the water awareness campaign by going to www.pace.edu/007 and read more editorials from students and staff here.