Green_Roof_Water_Monitoring_Report.doc - Green Roof Water...

This preview shows page 1 - 3 out of 18 pages.

Green Roof Water Quality and Quantity Monitoring Dr. Charles C. Glass Associate Professor Department of Civil Engineering Howard University and ETEC L.L.C. 6509 41 st Avenue University Park, MD 20782 July 26, 2007
Image of page 1

Subscribe to view the full document.

INTRODUCTION This project was designed to address the needs of the Chesapeake Bay Foundation (CBF), the American Society of Landscape Architect’s (ASLA), and the District of Columbia's Water and Sewer Authority by monitoring the performance of the ASLA green roof for water runoff reduction and water quality improvement. Under the National Pollutant Discharge Elimination System (NPDES), Municipal Separate Storm Sewer System (MS4), the government is tasked to utilize best management practice (BMP) methods to substantially minimize pollution transport from storm water runoff. Green roofs are being promoted as an optional BMP throughout the Washington D.C. Metropolitan area. The 3,000 sq ft ASLA green roof was installed in May of 2006 at its headquarters building on 636 Eye Street NW, Washington DC. It is one of seven green roof demonstration projects in the Anacostia River Watershed of DC that the Chesapeake Bay Foundation has partially funded with an incentive grant. ETEC monitored water quality and quantity on this roof for 5 rain events in the fall of 2006 and the spring of 2007. The sampling and monitoring of the green roof was performed in accordance with the standard operations for collection and measurement promulgated by the USEPA. In this study pH, temperature, total suspended solids (TSS), total dissolved solids (TDS), dissolved oxygen (DO), chemical oxygen demand (COD), and nutrients (ammonia, nitrite, nitrate, phosphate, and total phosphorus) were measured on rain water collected on the roof and runoff collected from the downspout from the green roof. Heavy metals (e.g. Cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb), mercury (Hg), arsenic (As)) were measured for two rain events to check for their presence. All of the samples were measured in triplicate to confirm the reproducibility of the results and the accuracy of both the equipment and the sampling methodology. The two primary goals of this project were to determine the reduction in runoff and to determine the concentrations of contaminants of concern leaving this green roof. Two flow meters were already installed on the roof of the ASLA building giving flow data for the water leaving the roof. ASLA collected the water in two clean collection jars provided by ETEC. ASLA staff and ETEC coordinated the collection and proper methodology to avoid human error in sample collection. A quantitative measure of the total flow or rainfall load on the roof was calculated by the known area of the roof and the acquired depth of rainfall. The duration of the sampling and monitoring effort for ASLA green roof was not to exceed 8 rain events or eight months from the notice-to proceed date. ETEC coordinated with CBF and ASLA to determine a schedule for sample collection and monitoring. In the end, since about 75% of the estimated rainfall did not pass through the green roof, 5 sample events were collected over 10 months.
Image of page 2
Image of page 3
  • Fall '14
  • ASLA

{[ snackBarMessage ]}

Get FREE access by uploading your study materials

Upload your study materials now and get free access to over 25 million documents.

Upload now for FREE access Or pay now for instant access
Christopher Reinemann
"Before using Course Hero my grade was at 78%. By the end of the semester my grade was at 90%. I could not have done it without all the class material I found."
— Christopher R., University of Rhode Island '15, Course Hero Intern

Ask a question for free

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern