Water Resources Research Act Program

Details for Project ID 2010TX356B

Trihalomethane Formation Potential in Rainwater Harvested from Different Roofing Materials

Institute: Texas
Year Established: 2010 Start Date: 2010-03-01 End Date: 2011-02-28
Total Federal Funds: $5,000 Total Non-Federal Funds: $10,000

Principal Investigators: Carolina Mendez, Kerry Kinney, Mary Kirisits

Project Summary: Rainwater harvesting systems are one way to address the worldwide increase in water demand. Although rainwater harvesting systems may be simple and inexpensive to construct, various sources of contamination can negatively affect water quality. Currently, we are sampling five pilot-scale roofs (asphalt fiberglass shingle, Galvalume metal, concrete tile, cool, and green) at the Lady Bird Johnson Wildflower Center in Austin, Texas to examine the effect of roofing material on harvested rainwater quality. Preliminary data show that harvested rainwater contains 2-37 mg/L dissolved organic carbon (DOC). If the harvested rainwater is for indoor use, it must be disinfected. If it is disinfected with chlorine, the presence of DOC can lead to the formation of harmful disinfection by-products such as trihalomethanes (THMs). The main purpose of the proposed work is to examine the trihalomethane formation potential (THMFP) of rainwater harvested from the pilot-scale roofs constructed of five different roofing materials.