Columbia University
OP-23: Stormwater Management

Columbia University emphasizes effective stormwater management in new construction as part of the university’s commitment to a standard of LEED Silver for new construction. There is a storm water diversion plan planned for the new Medical and Graduate Education Building, currently in design as well as implanting a vegetative marshland at the Campbell Sports Center. The stormwater management initiatives for new buildings work to optimize storm water management tactics based upon the LEED credits for stormwater under new construction, seeking a LEED-silver level or better. Additionally as part of the Manhattanville campus plan, with the campus so close to the Hudson River, stormwater management is a concern. An irrigation system and adding substantial greenscaping to a predominantly concrete area is part of the thoughtful stormwater management plan has been developed for the entire 17 acre campus as part of the LEED ND Platinum certification. Columbia is installing a new dedicated storm sewer and upgrading and relocating a combined (sanitary and storm) sewer to replace outdated 19th century sewage and water main systems in the Manhattanville area of West Harlem. The sewer project began in fall 2009 and is scheduled for an estimated completion in 2012 with a total project cost of $14.925 million. Project Benefits: • Improves the water quality of the Hudson River • Reduces flows to the local New York City wastewater treatment plant by an estimated 9.9 million gallons per year. This also saves energy at the plant. • Reduces the amount of combined sewage overflows (CSOs) discharged into the Hudson River by an estimated 1.6 million gallons per year. • Helps the PlaNYC goal of being able to use New York City’s rich network of waterways as recreational resources. • Consistent with the New York State Department of Environmental Conservation Hudson River Plan and the New York/New Jersey Harbor Comprehensive Conservation Plan. • Improves service to the community • Replaces and upgrades outdated sewage and water main systems – a legacy of 19th century municipal engineering found mostly in older cities like New York. • Relieves the pressure placed on the combined sewers during major rain events. • Reduces street flooding and building sewer back-ups. • Facilitates the upgrade of other utility services which will result in less service interruptions. In day to day operations, stormwater management is considered throughout the campus with green softscape an integral part of the urban city campus, walkways and sidewalks constructed with brick or paving stones that allow water to drain and greenroofs added to several buildings including the Office of Environmental Stewardship, GreenBorough residential brownstone, 118th St, a patch between Hartley and Hamilton, and Uris Library. There is also a rain barrel to collect and divert rain water away from the pavement that is used on the campus community garden on the Morningside campus. Columbia's Rain Barrels: http://gosustainable.blogspot.com/2010/11/rain-garden-is-coming-to-russell.html Manhattanville's Stormwater Management: http://neighbors.columbia.edu/pages/manplanning/pdf-files/current-construction-storm-sewer.pdf

The campus has green roofs on five of our buildings – we are the first institution of higher education in New York City to implement this technique as well as the first green roof research station. Zero Floor harvest sedum-a local plant from Upstate New York- supplies the greenroof and farm is within 2-300 miles of campus. The greenroofs are weeded once a year. On the CUMC campus there is a roof garden at Bard Hall, which helps divert rain water from the storm water system.

New construction projects will lay down permeable pavement where applicable to reduce the flow of contaminants into the city’s waterways. The Comer Lab’s parking lot on the LDEO campus is paved with such pavement and the 115th St parking lot on the Morningside campus permeates with its stone design. Additional opportunities for porous pavement are being considered such as part of the CUMC campus beautification plan, as well as within the new Medical and Graduate Education Building terrace, which is in design process. The construction of the new Comer Geochemistry Building required the relocation of an existing 85 car parking lot. Stormwater management originally required the construction of a new detention basin and 500 feet of drainpipe excavated through rock and the existing main campus thoroughfare. A porous asphalt infiltration design of alternative of 32,470 sf was installed that eliminated the drainpipe and detention basin, resulting in a zero net cost, 25% reduction in runoff, and 100% water quality treatment. LDEO's Porous Asphalt Parking Lot http://www.dec.ny.gov/lands/74995.html

Along the Lewisohn lawn, Chapel, and the Hudson River shore line along Baker Field, stone swales have been installed to divert water away from buildings and other walkways prone to flooding. The stone swales not only divert water, but slow down the water rate to allow for better groundwater recharge.

Catoniasta plants are installed on top of the stone near Lewisohn Hall. The plants operate as a vegetative swale by diverting water and slowing down the water rate to allow for better groundwater recharge.

Columbia’s Morningside campus employs a timed irrigation system. The Rain Bird irrigation system was installed on Lower Campus, College Walk and Low Plaza green spaces totaling about four acres. Columbia's irrigation grid with its 5,004 rotor heads is controlled and monitored by what's known as a cluster control computer. The customized system enhances campus environmental efforts by conserving water and power at about 20 percent. Over watering leaches nutrients, while under watering stresses the plant, which then becomes drought intolerant. Columbia's irrigation system: http://facilities.columbia.edu/new-irrigation-system-sustainable-coup-scorching-summer Manhattanville: http://neighbors.columbia.edu/pages/manplanning/pdf-files/current-construction-storm-sewer.pdf