Tijuana Sludge Management Study

Hazen and Sawyer assisted the Tijuana State Commission of Public Services in the development of the Tijuana Water and Wastewater System Modernization Project, evaluating sludge treatment and disposal alternatives for all current and future wastewater treatment plants and identifying a long-term sludge management solution compatible with the Tijuana Wastewater Master Plan.

Hazen and Sawyer assisted the Tijuana State Commission of Public Services (CESPT) in the development of the Tijuana Water and Wastewater System Modernization Project. One of the main components of the project was the Tijuana Sludge Management Study (SMS). The objective of the SMS was to evaluate sludge treatment and disposal alternatives for all current and future wastewater treatment plants, which serve more than one million people, and identify a long-term sludge management solution that is compatible with the Tijuana Wastewater Master Plan.

The major components of the SMS included:

Collection and Analysis of Existing and Future System Information
Characterization of Existing and Future Sludge
Sludge Production Projections
Review of Applicable Regulations and Norms
Development and Evaluation of Alternatives
Conceptual Design of Selected Alternative
Economic and Financial Feasibility Analysis
Development of an Implementation Plan

The selection of the proposed sludge treatment and disposal alternative was based on evaluation criteria which included socio-political, technical, reliability/complexity, operation/flexibility, market stability, normative, and environmental considerations. An evaluation matrix was developed in which alternatives were ranked using a point system; the alternative with the highest score was selected and the conceptual design and implementation plan were developed.

The selected alternative consisted of the transport, and subsequent treatment through lime stabilization, of approximately 190 tons/day of sludge at the Rosarito and Tijuana sanitary landfills as well as the San Antonio de los Buenos WWTP. Hazen and Sawyer also recommended that the client conduct pilot studies to further evaluate the feasibility of sludge reuse for the stabilization of side slopes of roads and streams, and the composting of sludge for agricultural applications.

In addition to the SMS, Hazen and Sawyer has assisted CESPT in conducting the Tijuana Telemetry System Study and the selection and design of the Popotla Wastewater Treatment Plant as part of the Tijuana Water and Wastewater Modernization Project.