Water and Wastewater Plant Engineer

Water and wastewater plant engineers plan, design, and oversee construction and operation of all processes and structures involved in the treatment, distribution, and collection of water and wastewater. These engineers work on a variety of scales, designing small package plants as well as large municipal and industrial treatment facilities, pumping stations, reservoirs, distribution systems, and sewers. Water and wastewater plant engineers can also be employed by municipal and industrial systems and plants to oversee day-to-day operation and maintenance.

Three workers with hardhats on looking at clipboards at a treatment plant

At a glance

Imagine you are sitting at a large drafting table studying the original construction drawings and process flow schematics of a wastewater treatment plant originally built in 1973. You are a water and wastewater plant engineer working for a consulting company that has been hired by the City to upgrade its main wastewater treatment plant. The facility must be retrofitted in order to deal with the growing volume of wastewater produced by residents and commercial customers, as well as to comply with increasingly strict regulations governing the treatment and discharge of wastewater to the environment. You and your team will design a plan for process optimization to treat more wastewater better and faster while staying within the City's size and budget constraints.

As a water and wastewater plant engineer, you specialize in designing new systems or upgrading existing facilities with new technology. In this case, your first task will be to identify problems and issues with the current plant's operation. For example, the plant's capacity will be reached within the next few years, so expansion is a big priority. There are also new effluent guidelines that have lowered acceptable levels for coliform discharge and other potential contaminants that will be difficult to meet with the current chlorine disinfection system.

You and your team will evaluate alternatives and new technologies to replace outdated equipment and address capacity and disinfection issues. Part of this evaluation involves preliminary costing for different alternatives, which involves not only determining the initial costs of equipment and installation, but also a lifecycle cost. The lifecycle cost analysis will give you an idea of a system's true cost: sometimes the best solution is not the one with the lowest initial cost because it may not last as long, may have higher maintenance costs, or may cost more to operate.

Once you and your team have evaluated options and chosen the improvements you want to build into the plant, you will develop a coordinated plan for construction and implementation. This can sometimes be the hardest part because the plan must allow for ongoing treatment while the work is being done. This is the city's main wastewater treatment plant, so it can't be taken off-line while its systems and equipment are upgraded. But when it is complete, your facility upgrade will increase capacity and ensure the wastewater treatment plant is meeting environmental regulations for years to come.

Job duties

Duties vary significantly from job to job, but the following list includes typical job duties one might encounter as a water and wastewater plant engineer:

  • Assess client needs and prepare conceptual design studies, including flowsheet development, equipment sizing, layout requirements, and capital and operating cost projections.
  • Design treatment facilities, pumping stations, reservoirs, and distribution and collection systems, and confirm designs using modelling techniques.
  • Prepare engineering reports, drawings, and specifications for water and wastewater projects.
  • Assist with or prepare applications for approvals and financial assistance on behalf of clients.
  • Participate in public presentations to make the public aware of the work and possible impacts during construction.
  • Perform inspections of water and wastewater facilities and prepare summary reports of findings, including cost estimates for repair.
  • Provide construction management on behalf of clients, including cost control, schedule reviews, and payment authorization.
  • Prepare and update facility operation and maintenance manuals.
  • Perform operations evaluations.
  • Participate in facility start-ups, operator training, and process and equipment troubleshooting.
  • Conduct health and safety inspections and report findings to managers.
  • Participate in staff meetings and meetings with the public to obtain input on neighbourhood concerns and problems.

Work environment

Water and wastewater plant engineers work in a variety of locations, including:

In the office:

  • Doing paperwork, analyzing data, and preparing reports
  • Drafting plans and models
  • Communicating on the phone and in meetings with clients, stakeholders, and government departments, and presenting designs and construction and operation reports to clients
  • Preparing proposals, tender documentation, and evaluation and project reports

In the field:

  • Touring and inspecting sites and managing inspection staff
  • Supervising installations and facility start-ups
  • Testing designs and recommended changes
  • Investigating complaints and recording data and observations
  • Supervising operations staff and coordinating maintenance schedules

Where to work

There are a number of places water and wastewater plant engineers can find employment. They include:

  • Engineering consulting firms
  • Federal, provincial/territorial, and municipal government departments
  • Public and private water and wastewater treatment facilities
  • Colleges, universities, and research institutes
  • Firms selling water and wastewater treatment equipment and chemicals

Education & requirements

If you are a high school student considering a career as a water and wastewater plant engineer, you should have strong marks or an interest in:

  • Mathematics
  • Physics
  • Chemistry
  • Calculus
  • Biology

In most cases, the minimum education requirement to work as a water and wastewater plant engineer is a university undergraduate degree.

If you are a post-secondary student considering a career as a water and wastewater plant engineer, the following programs are most applicable:

  • Mechanical Engineering
  • Civil Engineering
  • Environmental Engineering
  • Chemical Engineering

In order to work as a water and wastewater plant engineer, you must be registered as a Professional Engineer with your provincial association. Requirements for professional status vary among provinces.


A water and wastewater plant engineer at an entry level position makes an average salary of $40,275 per year in Canada.

With several years of education and experience, water and wastewater plant engineers can make between $50,500 and $85,000 per year.

Role Model

Bruce Boland

"It was during the early 1970s, when pollution of the Great Lakes was a major issue.” According to Bruce Boland, this is what persuaded him to complete a bachelor of science in engineering with a major in water resources. Originally, the University of Guelph student was looking to combine his experience of growing up on a farm with his strength in math and science to become an agricultural engineer. But after learning about the pollution in the Great Lakes, he made up his mind. "The need to clean up the pollution really caught my attention. It seemed like something that needed to be done, and I wanted to help.”

Today, the water and wastewater plant engineer is president of his own consulting company, Waterbru Water and Wastewater Services, in London, Ontario. Before 2002, when Bruce established the company, he worked for the Ontario Ministry of the Environment and the Ontario Clean Water Agency as a water and wastewater plant engineer. In a managerial role, Bruce oversaw the design and construction of new or upgraded water and wastewater facilities. "I looked at whether the components of the treatment plants were something the operators were going to be able to operate.” He also reviewed the specification documents detailing what equipment was being provided for new or upgraded plants.

In addition to the desktop review, Bruce met with the engineers creating the plant designs. "We would discuss things like the treatment plant capacity, meaning the volume of sewage or water it needs to treat.” He also met regularly with the municipality to discuss issues such as financing, staffing, and the capacity necessary for a facility’s growth over a 20-year time period. When touring new plants or existing plants that were being retrofitted, Bruce met with the construction team, and when construction was complete, he oversaw staff training on the new equipment. "One of the best parts about that job was being able to interact with such a broad range of professionals. I really enjoyed it.”

The primary drawback to Bruce’s work was the hurdles he often encountered working on government projects. "I can remember a couple of projects where I had to deal with several different municipalities, my own provincial department, and the federal government. It made getting the job done very difficult.” Regardless, Bruce persevered, always getting the job done. "I realized there was a need for what I did. A lot of people were depending on me to treat their water and wastewater.”