Background

CESPM operates the water and wastewater systems for Mexicali, Mexicali Valley and San Felipe, Baja California. The Mexicali wastewater system currently serves 299,364 connections with coverage reaching approximately 95.5% of households in the city. Wastewater treatment is provided through five plants with a combined maximum capacity of 2,164 liters per second (lps) or nearly 50 million gallons per day (mgd).

CESPM regularly conducts video inspections of its wastewater collection infrastructure and has identified aging and deteriorated wastewater collection lines requiring immediate repair or rehabilitation to prevent failures that could result in raw wastewater spills to the New River. Most of these pipelines are more than 30 years ago, have reached, or exceeded their expected useful life and are in immediate need of repair or replacement. When a sewer line collapses, untreated wastewater is typically discharged into the New River. In February 2022, a failure in the Las Arenitas force main caused a major spill resulting in 120.3 million gallons of sewage flowing into the New River. Since the New River flows from Mexico into the U.S. and discharges into the Salton Sea, the poor quality of the river flows reaching the Salton Sea may lead to health alerts in Imperial County, California.

To address this issue, CESPM developed a Strategic Wastewater Plan aimed at eliminating or reducing untreated wastewater discharges to the New River, prioritizing infrastructure rehabilitation activities and identifying potential funding sources. Immediate actions proposed under the plan include the rehabilitation of critical lift stations and replacement of approximately 54.8 miles of deteriorated concrete sewer lines. In 2020 CESPM initiated two projects currently under construction to replace 7.3 miles of pipeline and rehabilitate 15 lift stations.

Description

The proposed Project consists of replacing 13,243 meters (43,448 ft) of deteriorated sewer lines in 20 subdivisions within the Mexicali I and II service areas, which currently conveys an average of about 2.2 mgd.

The BEIF grant is targeted to address infrastructure in the Prohogar subdivision (14,616 ft. of 8-inch PVC pipe) and the Hidalgo subdivision (1,280 ft. of 15-inch and 1,532 ft. of 16-inch PVC pipe). However, depending on the availability of funds, additional areas may be funded by the BEIF grant.

Benefits

The rehabilitated infrastructure will improve system reliability by reducing the risk of pipeline failures that can cause sewage overflows onto local streets and into the New River, which flows northward into the United States. Specifically, the project will help protect public health and the environment by preventing approximately 96.8 liters per second (lps) or 2.2 million gallons per day (mgd)of wastewater discharges. As a result, the project will improve wastewater services for up to 11,624 existing residential connections.