Carollo Engineers is an environmental engineering firm specializing in the planning, design, and construction management of water and wastewater facilities for municipal and public sector clients in the United States. The firm is headquartered in Walnut Creek, California, and currently maintains 38 offices throughout the United States. Carollo has provided services to the City of Phoenix for over 80 years and to Southern California's Orange County Sanitation District for over 50 years. Carollo Engineers employs civil, structural, electrical, mechanical, environmental, and instrumentation and control engineers, as well as scientists, planners, architects, and CAD designers. Carollo offers water supply, treatment, and distribution engineering services; watershed and water resources planning; storm water and urban wet weather planning, permitting, and regulatory assistance; computer modeling, master planning, decision support analysis, and financial assistance services; and reuse studies. Carollo is also involved in planning and design of biogas cogeneration and standby power facilities for the water and wastewater industry; provides utility finance, business planning, asset management, infrastructure engineering, and water reclamation/reuse services; and provides program/construction management services for public work facilities and industrial and private structures. The company’s projects include pilot and treatment studies, pump stations, pipelines, solids handling facilities, and reservoirs. It serves public agencies, private developers, and industrial firms. Carollo has offices in Los Angeles, San Francisco, San Diego, Pasadena, Sacramento, Walnut Creek, Fresno, Bakersfield, Fountain Valley, and Riverside, California; Las Vegas and Reno, Nevada; Phoenix and Yuma, Arizona; Portland, Oregon; Seattle, Washington; Boise, Idaho; Salt Lake City, Utah; Broomfield and Littleton, Colorado; Kansas City, Missouri; Chicago, Illinois; Oklahoma City, Oklahoma; Charlotte, North Carolina; Dallas, Houston, Fort Worth, and Austin, Texas; Boston, Massachusetts; and Miami, Tampa, Orlando, Sarasota, Palm Beach, and Hollywood, Florida.