Wastewater Treatment System Design
Metra Consultation provides wastewater treatment system design and engineering support for residential, commercial, institutional, industrial, and municipal projects throughout Québec.
Where connection to a municipal sanitary sewer is unavailable, limited, or unsuitable, a properly designed wastewater treatment system is essential to protect public health, groundwater, surface water, and the surrounding environment.
Our multidisciplinary team develops practical, site-specific solutions based on wastewater characteristics, projected flow, soil and groundwater conditions, available space, discharge requirements, and applicable regulations.
Our Services
Our wastewater treatment engineering services may include:
- Preliminary site and project assessment
- Estimation of wastewater flow and design capacity
- Characterization of wastewater sources and anticipated loads
- Review of existing treatment systems and infrastructure
- Evaluation of soil, groundwater, and site constraints
- Selection and comparison of suitable treatment technologies
- Design of collection, pumping, treatment, and disposal systems
- Design of septic tanks and primary treatment components
- Design of advanced or secondary treatment systems
- Design of effluent polishing and disinfection systems
- Design of infiltration, dispersal, or controlled discharge systems
- Hydraulic calculations and process sizing
- Preparation of engineering plans, specifications, and technical reports
- Coordination with laboratories, municipalities, equipment suppliers, and contractors
- Support for municipal permits and MELCCFP authorization applications
- Construction support, commissioning, and site review when included in the mandate
Site-Specific Treatment Solutions
Wastewater treatment systems must be designed according to the actual conditions and demands of each project.
Our assessment may consider:
- Building use and occupancy
- Average and peak wastewater flows
- Wastewater composition and contaminant concentrations
- Seasonal or intermittent use
- Available land and site configuration
- Soil permeability and stratigraphy
- Groundwater elevation
- Distance from wells, watercourses, buildings, and property boundaries
- Topography and drainage conditions
- Sensitivity of the receiving environment
- Operation and maintenance requirements
- Future expansion or changes in use
These factors help determine the appropriate level of treatment and the most reliable method for managing the treated effluent.
Treatment Technologies
Depending on the project requirements, the proposed system may incorporate:
- Primary settling and solids separation
- Biological treatment
- Aerobic treatment units
- Media-based or filtration systems
- Membrane treatment technologies
- Nutrient-reduction processes
- Disinfection systems
- Pumping and flow-equalization systems
- Soil-based treatment and dispersal
- Advanced treatment for sensitive sites
- Monitoring and sampling components
Technology selection is based on treatment performance, site limitations, capital cost, operating requirements, maintenance needs, and regulatory criteria.
Existing System Assessment and Rehabilitation
Existing wastewater treatment systems may experience reduced capacity, hydraulic overload, equipment failure, odour problems, poor effluent quality, or inadequate performance following a change in building use.
Our team can assess the existing system, identify deficiencies, and develop recommendations that may include:
- Repair or replacement of damaged components
- Capacity upgrades
- Addition of treatment stages
- Improvements to pumping and flow distribution
- Rehabilitation or replacement of disposal fields
- Installation of monitoring or control equipment
- Conversion to an alternative treatment technology
- Connection to municipal infrastructure where feasible
The objective is to identify a technically sound and cost-effective solution that responds to current and future needs.
Multidisciplinary Engineering Coordination
Wastewater treatment projects often involve civil, geotechnical, structural, environmental, mechanical, and construction considerations.
Metra Consultation coordinates its civil, geotechnical, structural, and BIM teams to address:
- Soil suitability and infiltration capacity
- Excavation and groundwater conditions
- Tank and equipment foundations
- Access for construction and maintenance
- Underground utility conflicts
- Site grading and drainage
- Structural support for treatment equipment
- Equipment layout and BIM coordination
- Integration with existing buildings and infrastructure
This coordinated approach helps reduce design conflicts, improve constructability, and support efficient installation and long-term operation.
Our Process
Our typical process includes:
- Reviewing the project requirements and available site information
- Estimating wastewater flow and treatment loads
- Evaluating soil, groundwater, space, and regulatory constraints
- Comparing suitable treatment and disposal alternatives
- Developing the preferred treatment concept
- Completing hydraulic and process calculations
- Coordinating the design with other engineering disciplines
- Preparing plans, specifications, and technical documentation
- Supporting permit or environmental authorization applications
- Responding to comments from municipalities or reviewing authorities
- Providing construction and commissioning support when required
Information Typically Required
To begin the assessment, we may request:
- Topographic survey or certificate of location
- Architectural and site plans
- Proposed building use and occupancy
- Estimated water consumption or wastewater flow
- Existing system plans and maintenance records
- Soil and groundwater information
- Geotechnical or environmental reports
- Municipal correspondence and servicing information
- Laboratory results, when available
- Information regarding nearby wells, watercourses, wetlands, or sensitive areas
If information is missing, our team can identify the investigations, testing, or surveys required to proceed.
Why Choose Metra Consultation?
Metra Consultation offers coordinated civil, geotechnical, structural, and BIM expertise for wastewater treatment projects.
We are committed to providing:
- Responsive and professional service
- Site-specific and technically sound solutions
- Practical evaluation of treatment alternatives
- Coordinated multidisciplinary design
- Clear engineering plans and documentation
- Support throughout permitting and construction
- Solutions that consider performance, constructability, operation, and maintenance
Contact Us
Planning a project that requires an onsite, private, commercial, industrial, or municipal wastewater treatment system?
Contact Metra Consultation to discuss your project and develop a coordinated treatment solution based on your site conditions, capacity requirements, and regulatory obligations.