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Executive Management

Enrique Zaldivar - 245x300
Enrique C. Zaldivar, P.E.
Director and General Manager

Enrique has been at the helm of LA Sanitation & Environment (LASAN) as the Director and General Manager for over eight years. He was originally appointed in 2007, and then reappointed by Mayor Garcetti in September 2013.  LASAN is one of the largest agencies in the City of Los Angeles with nearly 3,300 employees and an annual revenue budget of over $1.1 billion. Through Mr. Zaldivar's leadership and management, LASAN oversees important environmental and infrastructure programs such as the City's Clean Water program, one of the largest in the world with its iconic flagship Hyperion Water Reclamation Plant; the Solid Resources program, which has achieved one of the highest recycling rates in the nation at 76.4% and climbing, and includes the recently implemented recycLA Franchise Initiative; and the Watershed Protection program, which is among the most innovative in the country with its use of green infrastructure for achieving water quality objectives for urban stormwater runoff, while delivering on multiple other benefits like open space, urban habitat support, and water supply.

Under Enrique's leadership, LASAN has had some very significant accomplishments of great benefit to the City at large, such as:

  • The adoption of the Low Impact Development Ordinance (LID), which brought in the expanded participation of the private sector for achieving stormwater quality and capture;
  • Successfully implemented the Single-Use Plastic Bag Ban Ordinance; 
  • Laid the policy groundwork for the adoption of the Solid Waste Private Hauler Exclusive Franchise Initiative; 
  • Made a persuasive case to the Mayor, City Council and the ratepayers for the approval  of a 10-year Financial Rate Plan for the City's Clean Water Program, providing financial stability and efficiency to one of the most critical  infrastructure programs of the City; 
  • Placed LASAN at the forefront of the larger City's strategy for water sustainability through its recycled water and watershed protection programs in alignment with Mayor Garcetti's Executive Directive No. 5 and City Council Policies;
  • Established a full-service Customer Care Center with 24/7 coverage to address customer requests at any time, in recognition of the fact that LASAN is a 24/7 operating agency and fully integrated with the MyLA311 system;
  • Successfully made the Solid Resources Program a Full Cost Recovery service as a quasi-Enterprise Fund with full accountability to the  ratepayers;
  • Implemented the brand new Clean Streets Initiative (CSI) through the leadership of the Mayor and City Council, with the ultimate goal of making  every corner of Los Angeles a clean, livable, and sustainable environment; 
  • Established a productive and collaborative Joint Labor/Management process across the entire organization where work issues get addressed and just as importantly, a process where innovation and work efficiency are fostered and promoted. 

Originally from the state of Zacatecas, Mexico, Enrique graduated from Azusa High School in the City of Azusa, attended UCLA long enough to have Bruin blood in him, and calls himself a proud Bronco from Cal Poly Pomona where he graduated as a Civil Environmental Engineer in 1985. He has also done graduate studies there and now serves as the Vice Chair of their College of Engineering’s Dean’s Leadership Board. Enrique is active in several organizations and serves on several of their Boards, including the Santa Monica Bay Restoration Commission, the National Association of Clean Water Agencies (NACWA), and others. He also serves on Cal Poly Pomona's School of Engineering Dean's Leadership Council where he has also been inducted into the Hall of Fame and honored as a distinguished alumni. Enrique has been honored by several organizations for his environmental leadership stewardship, including the Los Angeles Conservation Corps (LACC), Friends of Ballona Wetlands, Heal the Bay, Community Conservation Solutions, and others.  Enrique also has an interest in furthering the relationship between the U.S., Mexico and Canada by sharing industry best practices and technical exchange missions between the three countries.

Enrique started his career with the City of Los Angeles in 1985 straight out of college as an associate engineer. Twenty-two years later, he became the General Manager of LA Sanitation and Environment.

Enrique and his wife, Brenda, have three children: Enrique Jr., Alonzo, and Carina.

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Traci J. Minamide, P.E., B.C.E.E.
Chief Operating Officer
Traci assists the Director in LASAN’s activities with an emphasis on wastewater treatment and water reclamation. She has been with the City for over 25 years serving in many capacities including water planning, industrial pretreatment, environmental regulations, wastewater treatment, biosolids and water reclamation.

Traci holds a Bachelor of Science degree in Civil Engineering from California State Polytechnic University at Pomona, a Master of Science degree in Environmental Engineering from Loyola Marymount University and certification in Executive Management for State and Local Government from Harvard University. She is also a licensed professional civil engineer in the State of California and a Board Certified Environmental Engineer through the American Academy of Environmental Engineers and Scientists. She serves on the Board of Directors for the California Association of Sanitation Agencies (CASA) and the State’s Advisory Panel on Direct Potable Reuse.
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Lisa B. Mowery, P.E.
Chief Financial Officer
During her 24 years with the City of Los Angeles, Lisa has worked as a project manager and environmental compliance specialist. During the past 16 years, she has been involved in the issuance of over $4 billion in bonds for the City's Wastewater Program. Lisa also specializes in rate-setting and led an effort for the wastewater program resulting in the adoption of sustainable wastewater fees for a ten-year period.  She currently manages LA Sanitation’s financial programs, totaling more than $1 billion in annual revenues. She has a Bachelor of Science degree in Civil Engineering from Purdue University and is a Registered Civil Engineer in California. She currently manages LASAN's administration and financial programs.
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Mas Dojiri, Ph.D., B.C.E.S.
Assistant Director
Mas oversees the Technical Services Divisions, which is comprised of Environmental Monitoring, Industrial Waste Management, Regulatory Affairs, Information Control Systems, and Industrial Safety Compliance Divisions. He is also designated as the Chief Scientific Officer for LA Sanitation and serves as a member of the Board of Governors and the Joint Strategic Advisory Team of the Southern California Coastal Ocean Observing System (SCCOOS). He also serves as the Vice-chair of the Technical Advisory Committee of the Santa Monica Bay Restoration Commission, and served as both the Chair and Vice-chair of the Board of Commissioners for the Southern California Coastal Waters Research Project.  Mas is also currently the Chair of the Environmental Biology subcommittee of the American Academy of Environmental Engineers and Scientists and was instrumental in creating the national Board Certification for Environmental Scientists.  Mas received his BA from UC Santa Barbara, his MA from California State University, Long Beach, and his PhD from Boston University.  He completed his postdoctoral fellowship at the National Museum of Natural History, Smithsonian Institution and is the author of 38 peer-reviewed scientific publications and two technical books on crustaceans.
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Alex E. Helou, Ch.E.
Assistant Director
Alex heads the Solid Resources Group that is responsible for managing solid waste for the entire City of Los Angeles, including collection, transport, and processing of source separated recyclables, green materials, and municipal solid waste from 750,000 residential customers. Alex leads a workforce of over 1,300 employees in five Divisions, with an annual operating budget of over $180 million. He is in charge of implementing many key solid waste management strategies to help the City of Los Angeles achieve Zero Waste by 2025, including the Solid Waste Integrated Resources Plan and the Commercial Franchise System. The City has exceeded the 75% diversion rate and continues moving toward the zero waste goal. A 22-year veteran of the City of Los Angeles, Alex is a registered Chemical Engineer with a Master's degree in Environmental Engineering
Jose "Pepe" Garcia
Assistant Director

Jose “Pepe” Garcia serves as the Assistant Director of Solid Resources Operations.

Pepe began his 30-year career with LASAN as a Refuse Collection Truck Operator in the West Los Angeles Yard. He has worked as a Crew Instructor, Supervisor in Safety and Training, Alternative Fuel Program, and Container Replacement, Superintendent at Customer Care and North Central and Solid Resources Manager at Clean Streets LA.

Most recently, Pepe was in charge of the Solid Resources Collection Divisions.

Tim D.
Timeyin Dafeta, P.E.
Executive Hyperion Plant Manager
Tim is the Plant Manager of the City of Los Angeles Hyperion Water Reclamation Plant
Hyperion is one of the largest plants in the world with an annual operating budget of over $80 million, annual capital budget of over $40 million, and staff of 372 employees of all trades and professional classes.

During his 29 years with the City of Los Angeles, he has worked in process engineering, capital projects planning, industrial pretreatment, environmental regulations, wastewater treatment, and biosolids management. Tim is a licensed civil engineer with the State of California and has a Master’s degree in Applied Math.