Request for Proposals for Engineering Design Services for Chlorine Conversion Project - Gaseous Chlorine Feed System to Liquid Hyprochlorite Feed System

The City of Calexico (“City”) is requesting proposals from qualified engineering professionals to provide engineering design services for Chlorine Conversion Project – Gaseous Chlorine Feed System to Liquid Hypochlorite Feed System. The City proposes to convert from a gaseous chlorine system to a 12.5% bulk sodium hypochlorite disinfection system.

The City owns and operates a Water Treatment Plant (“WTP”) and Eastside Water Reservoir (“EWR”). The WTP receives its water supply from the Colorado River through the Imperial Irrigation District’s (“IID”) canal. The City’s WTP has a design capacity of 14 Million Gallons per Day (“MGD”), with an average daily demand of 7-8 MGD and current peak flow of 9 MGD. The EWR has a design capacity of 6 MGD, with an average daily demand of 1.25 MGD. Both the WTP and EWR currently operate on gaseous chlorine water disinfection system to disinfect the water prior to distributing it through the City’s supply lines. The City has concerns regarding the usage of chlorine gas as a disinfectant, as chlorine gas is toxic and poses dangers to the public and operations staff. The WTP is located adjacent to residential and commercial areas, schools and the Calexico International Border and the EWR is located adjacent to residential area. Both facilities pose a significant high risk of chlorine gas exposure to the public.

The contract will be regulated according to the provisions of all federal, state and local laws and ordinances that are applicable. This includes compliance with prevailing wage rates and their payment in accordance with California Labor Code, Section 1774. All Service Providers and sub-consultant(s) shall pay all workers not less than the general prevailing rate of per diem wages and the general prevailing rate for holiday and overtime work as determined by the Director of the Department of Industrial Relations, State of California, for the type of work performed and the locality in which the work is to be performed, pursuant to sections 1770 et seq. of the California Labor Code. Prevailing wage rates are available on the Internet at: http://www.dir.ca.gov. All Service Providers and sub-consultant(s) shall comply with the registration and qualification requirements pursuant to sections 1725.5 and 1771.1 of the California Labor Code.

Consultant must submit five (5) copies of their proposal with original Consultant signature. The proposal must be formatted in accordance with the instructions of this RFP. Promotional material may be attached, but are not necessary and will not be considered as meeting any of the requirements of this RFP. Proposals must be enclosed in a sealed envelope or package, clearly marked “RFP for Engineering Design Services for Chlorine Conversion Project – Gaseous Chlorine Feed System to Liquid Hypochlorite Feed System” and delivered on or before 2:00p.m. on Thursday, April 30, 2026 to:

Office of the City Clerk

City Hall

City of Calexico

608 Heber Avenue

Calexico, CA 92231

Late, emailed or facsimile proposals will not be accepted. It is the proposer’s responsibility to assure that its proposal is delivered and received at the location specified herein, on or before the date and hour set. Proposals received after the date and time specified will not be considered.

Copy of the Request for Proposals can be obtained at the Public Works Department, 549 Pierce Avenue, Calexico, Calexico, California 92231 or by visiting the City of Calexico website at www.calexico.ca.gov.

Consultant will be required to obtain a City of Calexico Business License once proposal is awarded.

If you have any questions or require additional information, please do not hesitate to contact the Public Works Department at 760/768-2160.

Jesus Villegas Peimbert

Public Works Director/City Engineer

City of Calexico