Keli Callahan - Las Vegas, NV 

Joining the firm in 2001, Ms. Callahan’s expertise in water and collection system planning, hydraulic modeling, project design, and construction management. She is skilled in water distribution and wastewater collection hydraulic computer modeling software, AutoCAD, and geographic information systems (GIS). She holds a Bachelors Degree in Civil Engineering from California State University-Fresno.  

Darryl Corbin - Dallas, TX

Mr. Corbin has 27 years of progressive engineering experience, serving in the roles of project engineer, project manager, principal-in-charge, and office manager. His experience encompasses studies, master planning, design, and project management for water treatment plants, wastewater treatment plants, pump stations, transmission pipelines, water distribution systems, and wastewater collection systems.  He holds a Bachelors Degree in Civil Engineering from the University of Queensland–Australia; a Bachelors Degree in Civil Engineering and a Masters Degree in Business Administration from the University of Texas–Arlington.

Rajesh Doppalapudi - Orange County, CA 

Mr. Doppalapudi is a civil engineer experienced in analysis and design of water and wastewater projects.  He has worked as a process engineer on numerous projects involving wastewater, solids handling and disposal with emphasis on thickening and dewatering processes. He is a graduate from the Indian Institute of Technology–Bombay in Civil Engineering and holds a Masters Degree in Environmental Engineering from the University of Cincinnati.

Kirk Gardiner - Phoenix, AZ 

Mr. Gardiner has 25 years experience in mechanical design engineering, plant operations and maintenance work, specification development, equipment acquisition, and contract administration.  He has worked on several water and wastewater projects with clients such as the City of Phoenix and the City of Mesa, Arizona.  He is a graduate of Northern Arizona State University with a Bachelor Degree in Mechanical Engineering.

Andrew Gilmore - Phoenix, AZ 

Mr. Gilmore is an accomplished civil engineer with 12 years of consulting experience including professional experience in project management, wastewater process and design, water system process and design, civil site design, environmental remediation and investigations/ delineations, hydrogeologic investigations and interpretations. His experience also includes permitting for water and wastewater projects. He holds a Bachelors Degree in Engineering Geology from State University of New York-Stony Brook and a Masters Degree in Water Engineering from California Polytechnic State University-San Luis Obispo.

Stephen Grooters - Denver-Broomfield, CO 

Mr. Grooters has been involved in water and wastewater engineering services throughout his academic and professional careers.  Including conducting research at the University of Colorado to determine optimal pretreatments for Colorado River Water nanofiltration.  He has served as project manager and project engineer for projects in Colorado and the Midwest.  He holds a Bachelors Degree in Environmental Engineering from Michigan Technology University and a Masters Degree in Civil Engineering/Environmental Water Resources from the University of Colorado. 

Jose Gutierrez - Fresno, CA 

Mr. Gutierrez has over 14 years of professional experience in performing engineering studies and infrastructure design of public work utilities and related projects. He has served as a skilled project manager, project engineer, and technical reviewer on water and sewer system master plans and wastewater treatment plant designs.  His experience also includes the preparation of complete master plan reports and studies, and knowledge of state-of-the-art water distribution and wastewater collection hydraulic computer models.  He is a graduate of the University of California–Berkeley with a Bachelors and a Masters Degree in Civil Engineering.

Erik Jorgensen - Orange County, CA

Mr. Jorgensen is a senior civil/chemical engineer with 20 years of experience in a variety of challenging water and wastewater issues ranging from conventional and innovative process engineering approaches to regulatory compliance. His experience includes water quality assessment; hydraulic modeling; preliminary and final design of treatment and collection systems; and stormwater, drinking water, wastewater, and air permitting. He has experience with the development of stormwater pollution prevention plans, spill control plans, and emergency response plans pursuant to local and regional regulations. His wastewater treatment experience includes the use of chemical treatments (precipitation, oxidation), physical treatments (filtration, microfiltration, and ultrafiltration), and biological processes. He holds a Bachelors Degree in Chemical Engineering from the University of Cincinnati and a Masters Degree in Chemical Environmental Engineering from the University of Arizona.

Becky Luna - Denver-Broomfield, CO

Ms. Luna has served as project manager and project engineer in the southwest region.  She is skilled in the preliminary and final design of municipal wastewater treatment facilities with work involving unit process evaluation, new facility layout and retrofitting of existing facilities. Her primary area of focus has been in secondary treatment and anaerobic digestion facilities, including the design of advanced two-phase digestion processes and evaluation of digester mixing alternatives. She is a graduate of the University of Illinois with a Bachelors Degree in Civil Engineering and a Masters Degree in Environmental Engineering.

Sandeep Sethi, Ph.D. - Sarasota, FL

Dr. Sethi has 17 years of experience in water and wastewater treatment and is a nationally recognized expert in desalination and membrane technologies. He has been responsible for project management and process engineering/design activities for numerous successful projects, where he has served in the roles of project manager, principal investigator, technical advisor, project engineer, or lead process engineer. In the project delivery role, he has been responsible for successful completion of projects that span diverse expertise including planning, process engineering, design, applied research, and technology testing and operations (including full-scale, bench, and pilot).  In addition, he has extensive experience in advanced treatment technologies, and in particular a thorough understanding of membrane treatment and desalination technologies.

In 2006, he was selected to the National Research Council (NRC) Committee of the National Academies to contribute to “Advancing Desalination Technology,” which will serve to make recommendations to the nation and Congress on the future direction and implementation of desalination technology.  He holds a Bachelors Degree in Civil Engineering from Birla Institute of Technology and Science–India, and a Masters Degree and Doctorate Degree in Environmental Engineering from Rice University–Texas.

Tim Taylor - Sacramento, CA 

As a senior infrastructure manager with Carollo Engineers, Mr. Taylor has served as project manager for numerous water and wastewater infrastructure and treatment projects. With 23 years of experience, his skills include engineering design, construction, and project management for water distribution systems, gravity sewer collection systems, pump stations, water and wastewater treatment facilities, geographic information system (GIS) and modeling projects.  In addition, he is experienced in all aspects of management, technical engineering, modeling, GIS, and design software. He holds both Bachelors and Masters Degrees in Civil/Environmental Engineering from the California Polytechnic State University–San Luis Obispo and San Jose State University respectively.

Mike Warriner - Walnut Creek, CA 

As a senior construction manager, Mr. Warriner’s experience involves the management and administration of construction projects for the firm.  He is skilled a skilled administrator which includes overseeing field staff, interfacing with clients and conducting pre-bid conferences.  He has also served as senior engineer and operations superintendent for the Contra Costa Water District (CCWD) in Concord, California. He holds a Bachelors Degree in Architectural Engineering from the California Polytechnic State University.

Inge Wiersema - Pasadena, CA