Leigh is the principal of Greywater Corps, a company that designs, installs, and teaches about greywater irrigation and rainwater harvesting systems as a solution to California’s water crisis. He has installed hundreds of systems throughout the Los Angeles area, ranging from simple gravity-flow systems to 1000 gallon-per-day fully automated treatment systems and massive underground cisterns. Leigh also works with nonprofits, water purveyors and city agencies to facilitate broader implementation of greywater use. He has lectured or taught workshops at numerous institutions, local and statewide. Leigh is licensed as an architect, general contractor, and plumber in the state of California, and is an ARCSA Accredited Professional.