Background

COMAPA provides water and wastewater services to the municipality of Miguel Aléman. Approximately 87% of the homes in its service area are connected to the wastewater collection system, which collects an average of 50 liters per second (lps) or 1.14 million gallons per day (mgd) of wastewater. The wastewater flows are conveyed to a lagoon-based treatment plant with a total capacity of 75 lps (1.71 mgd). The plant effluent currently complies with the quality standards established in Mexican regulation NOM-001-SEMARNAT-1996 and is discharged to the Guardados Canal to be reused in agriculture.

The El Mirador, Montebello and Los Presidentes subdivisions located in the southern part of the city do not have wastewater collection lines, so their residents use on-site disposal systems such as latrines, cesspools, and septic tanks to dispose of their wastewater. Many of the systems are substandard and do not function properly, posing a potential risk for soil and groundwater contamination that could ultimately affect the water quality of the Rio Grande River. Continuous leaks and seepage of untreated or inadequately treated wastewater also generate significant risks to human health.

To remedy this situation, COMAPA is proposing to extend its wastewater collection system to serve these three subdivisions.

Description

The project consists of constructing a wastewater collection system in the El Mirador, Montebello, and Los Presidentes subdivisions in the southern area of the city of Miguel Aleman, and includes the following components:

• Sewer Main 1: Installation of approximately 3,875 meters (12,713 ft) of polyvinyl chloride (PVC) pipe with diameters ranging between 10 and 18 inches, and construction of two sedimentation boxes.
• Sewer Main 2: Installation of approximately 693 meters (2,274 ft) of 8-inch PVC pipe, which includes crossing a canal.
• Sewer lines: Installation of approximately 16,500 m. (54,134 ft) of 8-inch PVC pipe and 274 m. (899 ft) of 10-inch PVC pipe.
• Residential connections: Installation of approximately 500 residential wastewater connections, including the decommissioning of the corresponding on-site wastewater disposal systems.

BEIF funding is expected to be used for the construction of sewer main No. 1 and the residential connections, while Mexican funds will be used to build the wastewater collection system, sewer main No. 2, and a canal crossing that is necessary for the operation of the system.

Benefits

The project will provide first-time wastewater collection and treatment services to approximately 500 existing homes in three subdivisions, eliminating the risk of soil and groundwater contamination from substandard on-site sanitary systems, as well as prevent untreated wastewater flows to transboundary water bodies such as the Rio Grande River. Specifically, the project will collect and convey 3 lps (68,473 gallons per day) of wastewater to the municipal water treatment plant.