Please CLICK links below to view some of our recent projects in these categories:

Wastewater Treatment and Water Recycling	Water  Treatment	Water Reservoirs  & Well Heads	Pumping Stations	Pipelines	Electrical and Instrumentation & Controls	Construction Management
:: WASTEWATER TREATMENT AND WATER RECYCLING
Headworks and Grit System Improvement Project, Point Loma Wastewater Treatment Plant (PLWTP), City of San Diego, CA   As Prime Consultant, LEE & RO planned, engineered and designed a $25 million Headworks & Grit System Improvement project at the 240 mgd PLWTP.  LEE & RO’s scope included physical model building and field-testing of the existing headworks to optimize the flow distribution, to develop a reliable hydraulic profile, and to determine the most-efficient grit tank cross-sectional dimension configuration.  The project includes reconfiguration of the south aerated grit tanks, a new two-storey grit dewatering building, odor control system upgrading, and improvements to the influent flow distribution.  The new grit dewatering building is 40 feet wide, 140 feet long and 49 feet high and houses seven SlurryCup grit separators/grit washers/grit storage bins, an electrical room, foul air fans, and a grit trucking facility.  Due to extremely congested site conditions, an extensive constructability analysis was performed.  The project design is scheduled to be complete in June 2009 and the construction to start November 2009.
Wastewater Treatment Plant Expansion and Improvements, Valley Sanitary District, Indio, CA   As Prime Consultant, LEE & RO has been responsible for the process analysis, development of a master plan, preparation of plans & specifications, as well as bidding and construction management services for a $49 million plant expansion and improvements project that is being implemented in two phases.  The $24 million Phase 1 Liquid Train project, which has been in operation since November 2008, increased the activated sludge plant capacity from 5 to 10 mgd.  The Phase 1 project included retrofit of existing aeration tanks, new aeration blowers, new secondary clarifiers, new chlorine contact tanks, a new 54-inch outfall, and two sludge dewatering belt presses.  The $25 million Phase 2 Solids project will include new vortex grit removal, new primary clarifiers, gravity belt waste activated sludge thickening, anaerobic digestion, and a cogeneration system.  The Phase 2 project design is scheduled to be complete in 2009 and the construction will begin July 2010.
Wastewater Treatment Plant Upgrading,  City of Brawley, CA As Prime Consultant, LEE & RO is responsible for process analysis, preparation of a project report, preparation of plans & specifications, as well as bidding and construction management / resident engineering services for a $25 million plant upgrading and improvements project at the 5.9 mgd wastewater treatment plant.  LEE & RO successfully assisted the City to obtain $15 million funding from the Clean Water State Revolving Fund (CWSRF) and $10 million grant from the American Recovery & Reinvestment Act (ARRA) fund.  The project components include activated sludge process complete with new blowers and secondary clarifiers and sludge dewatering facilities.  The sludge dewatering facilities include a gravity thickener, a centrifuge, and a solar greenhouse for sludge drying.  The project design has been complete and the construction is scheduled to start November 2009.
Headworks Replacement, Hill Canyon Wastewater Treatment Plant, City of Thousand Oaks, CA As Prime Consultant, LEE & RO has been responsible for engineering analysis, preliminary design report & final design documents, and the engineering services during construction for rehabilitation and upgrading of the North and South Headworks at the 14.5 mgd Hill Canyon Wastewater Treatment Plant.  The rehabilitation of the north headworks, which was offline, included replacement of the augers with mechanically-cleaned bar screens and screenings compactors, installation of new air and grit pumping systems, addition of walkways and grit tank covers, and upgrading of the electrical and control systems.  The rehabilitation of the south headworks included replacement of the existing Infilco Degremont climber screens with Huber step screens and screenings conveyors and compactors, and upgrading of the electrical and control systems.  The project also includes the replacement of piston-type primary sludge pumps with progressive cavity or gear pumps.  The design is scheduled to be complete in September 2009.
Trancas Water Pollution Control Plant (TWPCP),  Los Angeles County Department of Public Works, CA TWPCP, built in 1963, consists of the headworks, influent pump station, primary clarifiers, rotating biological contactor (RBC), aerobic digester, sand filters, and effluent leachfields.  As Prime Consultant, LEE & RO upgraded the 0.3 mgd plant, prepared an engineering report, prepared final design, provided engineering services during construction, and assisted the County in securing the State Revolving Fund (SRF) financing.  Plant upgrades included the headworks, influent pump station, equalization basins, extended air aeration activated sludge with anoxic selectors, dual media filters, and chlorination.  LEE & RO also designed monitoring wells and provided the ground water quality monitoring services.  The $3.9 million project construction was completed in 2008.
Water Reclamation Plant No. 4 Expansion,  Coachella Valley Water District, Coachella, CA As Prime Consultant, LEE & RO provided engineering, design and construction management& resident engineering services for a $21 million project which increased the secondary treatment plant capacity from 6.9 to 9.9 mgd.  Project components included two BiolacTM activated sludge basins, two secondary clarifiers, a blower building with Turblex aeration blowers, an emergency generator, a gravity belt thickener, a sludge dewatering building with a belt press, chlorine contact tanks, and chlorine and sulfur dioxide storage & feeding system.  The construction was completed in 2008 and the plant has been in operation.
Wastewater Treatment Plant Phase 1, Phase 2, and Phase 3 Expansion/Improvement Projects, City of Patterson , CA As Prime Consultant since 1999, LEE & RO has planned, designed, and managed construction for several plant expansion projects.  The $6 million Phase 1 Expansion/ Improvement project increased capacity from 0.5 to 1.3 mgd in 2003 and the $10 million Phase 2 Plant Expansion/Improvement project further increased capacity from 1.3 to 2.0 mgd in 2006.  The plant, which is capable of nitrogen removal, consists of headworks, oxidation ditch activated sludge, and percolation ponds.  In June 2009, LEE & RO completed the design of an $8 million Phase 3 Expansion project to increase the plant capacity from 2.0 to 2.75 mgd.  LEE & RO is currently designing a $2 million sludge dewatering centrifuge project.
Wastewater Treatment Plant Rehabilitation and Improvements,  Sacramento Regional County Sanitation District (SRCSD) The SRCSD Regional Plant treats average flows of 154 mgd and peak flows of 320 mgd.  The master planned ultimate facilities included five new aerated grit removal tanks, ten 120-foot diameter circular clarifiers, a grit dewatering building, an odor control facility, and an electrical substation & building.  As Prime Consultant, LEE & RO analyzed plant hydraulics, methods to improve aerated grit tank efficiency, grit transport piping, grit dewatering and truck loading concepts, and odor control systems.  Subsequently, LEE & RO designed a $5 million aerated grit removal tank improvement project that also included modification of the headworks/primary clarifier influent hydraulics.  The $5 million improvement project construction was completed in 2006 and LEE & RO is currently designing modifications to the grit transport system.
Rehabilitation and Modification of Anaerobic Digesters, Wastewater Treatment Plant No. 1 and No. 2,  Orange County Sanitation District, Fountain Valley, CA As Prime Consultant, LEE & RO prepared a preliminary design report, plans and specifications, and provided engineering services during construction for an $11 million digester improvements project for the 274 mgd Treatment Plant No. 2 (Project No. P2-39).  Plant No. 2 has 20 digesters.  The P2-39 project included rehabilitation of 7 digesters and 4 digester control buildings.  Project elements included electrical & control system upgrading and automation, addition of sludge flow meters and control valves, sludge and digester gas piping, and structural rehabilitation.  P2-39 construction was completed in 2004.  As subconsultant to AECOM, LEE & RO has been responsible for electrical and instrumentation & control system engineering, design, and construction phase services for the $40 million Digester Improvement project at the 176 mgd Treatment Plant No. 1 (Project No. P1-100).  Project No. P1-100 will rehabilitate all 12 digesters at Plant No. 1 to increase the capacity to process additional solids from the new full-secondary facilities.  The P1-100 design is complete and the construction is scheduled to start in December 2009.
MBR Process Study, Water Quality Control Plant,  City of Riverside, CA As Prime Consultant, LEE & RO authored a membrane bioreactor (MBR) feasibility study for the 40 mgd wastewater treatment plant, which consists of two activated sludge plant trains.  The objective of the MBR study was to find the most cost effective alternative to expand the treatment plant capacity from 40 to 50 mgd.  The scope of work included evaluation of available MBR technologies, development of MBR design criteria, construction cost estimate, and a preliminary site adaptation plan. The study reviewed the capacities of the unit processes and recommended that the City convert portions of the Plant 1 activated sludge to a MBR process at an estimated construction cost of $50 million.  The study was completed in 2007.
Wastewater Treatment Plant Expansion,  City of Holtville, CA As Prime Consultant, LEE & RO was responsible for process analysis, planning, and preparation of an engineering report for the City’s treatment plant expansion from 0.8 to 2.2 mgd.  The secondary NdeN processes under study included conventional activated sludge, oxidation ditch, single-cell activated sludge (Biolac), and SBR. The treatment processes also include new headworks, filtration, and UV disinfection.  The total project cost for the 2.2 mgd NdeN plant is estimated at $11 million.  The study was completed in 2007 and the final design is scheduled to start as soon as the funding is arranged.
Rehabilitation of Primary Clarifiers and Odor Control Systems, Wastewater Treatment Plant No. 2,  Orange County Sanitation District, Fountain Valley, CA As the Principal Subconsultant (35% share of contract value) to Malcolm Pirnie, LEE & RO is responsible for electrical and instrumentation and control (I&C) system engineering, design, and construction phase services for a $55 million plant rehabilitation project at the 274 mgd Plant 2.  Under this project, all fourteen 140-foot diameter primary clarifiers, seven primary sludge pump stations, and the North and South Scrubber Complexes will be refurbished and upgraded.  The design was completed in 2007 and construction is scheduled to be complete in early 2010.
Water Reclamation Plant Phase I and Phase II Expansion,  City of Angels, CA As Prime Consultant, LEE & RO was responsible for the planning, design and construction management services for the $3.5 million Phase I and the $4.5 million Phase II Expansion projects.  These projects process the wastewater generated from this fast growing community.  The $8 million expansion projects included new grit removal, sequencing batch reactors (SBRs), a blower building, chlorination system, aerobic digestion, and utility and site improvements.  Construction for the Phase II facilities was completed in 2007.
Wastewater Treatment Plant Cyanide Engineering Report,  City of Calipatria, CA The City was experiencing violations of free cyanide discharge limitation of the NPDES permit at their 1.9 mgd wastewater treatment plant.  As Prime Consultant, LEE & RO reviewed cyanide analysis test protocols as well as the cyanide source identification and characterization.  Also, LEE & RO investigated potential free cyanide formation within the plant’s treatment processes (e.g. chlorination & dechlorination).  LEE & RO took samples and had three labs provide independent analytical data based on the approved test protocols.  The report recommended improved sampling, follow correct analysis procedures, and implement industrial source controls.  The Regional Water Quality Board accepted the report and no more cyanide violations have been cited after the City adopted the procedures recommended by the report.
Wastewater Treatment Plant Improvements,  Regional Plant 2, Inland Empire Utilities Agency, Chino , CA As Prime Consultant, LEE & RO is responsible for process analysis, preparation of the project report, preparation of plans & specifications, bidding, and construction management services for $5 million in improvements.  Improvements will be made to solids processing trains such as automation of the dewatering centrifuge operation, retrofit of the cake conveyor system, improvements to gravity and dissolved air floatation thickeners, centrate pumping optimization, and a new septage receiving station.  The construction is scheduled to be complete in late 2009.
Wastewater Interceptor Sewer Odorous air Treatment Facilities,  City of Los Angeles, CA As the Principal Subconsultant to Black & Veatch, LEE & RO is responsible for preliminary design, final design and construction support services relative to the mechanical, electrical, and instrumentation systems for Odorous Air Treatment Facilities (ATFs) for the City of Los Angeles’ interceptor sewers.  Two ATFs are under construction and the third under design.  The total construction value of the three ATFs is approximately $20 million.

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