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Authors Posts by Shaina Jones

Shaina Jones

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Kingston, Ont. sewer rehabilitation using steam cured in-place lining. Over three kilometres of pipe was lined, across environmentally sensitive areas. Click to enlarge.

By Dr. Mark Knight, Doug Onishi and Jason Johnson

Kingston, Ont. sewer rehabilitation using steam cured in-place lining. Over three kilometres of pipe was lined, across environmentally sensitive areas. Click to enlarge.
Kingston, Ont. sewer rehabilitation using steam cured in-place lining. Over three kilometres of pipe was lined, across environmentally sensitive areas.
Click to enlarge.

Canada’s water pipeline infrastructure is aging and deteriorating. According to the first Canadian Infrastructure Report Card 2012, the total replacement cost of drinking water systems is $68.6 billion. Water distribution and transmission pipelines account for over $50 billion, or 73% of the replacement value. The cost to replace Canada’s wastewater collection system is estimated at $70 billion, with pipelines accounting for approximately 79% of that.

Fixing, renewing and replacing this critical infrastructure is essential for Canada’s well-being and economic prosperity.

Trenchless technologies are a series of construction methods that have been developed to repair, renew and replace pipelines without the need for continuous excavations. Over the past 20 years these innovative construction techniques have grown in use. They have shown cost savings of up to 40%, when compared to open cut replacement, while reducing greenhouse gas emissions by 80% – 100%.

Founded in 1994, the Centre for Advancement of Trenchless Technologies (CATT) and its membership of university, municipal and industry representatives, are committed to the advancement of knowledge, materials, methods and equipment used in trenchless technologies. CATT’s efforts and activities include technology transfer initiatives, such as specialized training sessions, a biannual trenchless roadshow, research and material testing, development of trenchless specifications and industry networking.

CATT is also working to address the need for a standardized watermain defect coding and condition rating system. Generally, municipalities manage their watermain rehabilitation program based on break history, water quality improvement, or capacity needs, with no standardized methodology.

In 2013, the Water Research Foundation (WaterRF) put out a request for proposals to develop a potable water pipeline defect condition rating system. Dr. Mark Knight, executive director of CATT, Dr. Rizwan Younis, Dr.Yehuda Kleiner and others teamed up to win the assignment.

The project’s goal is to develop an industry-accepted standard, which will allow all cities in North America to speak on common terms and to determine which pipes need to be fixed and when. It will also lay the foundation for North America’s water utilities to determine the real cost of the water infrastructure backlog and deficit, which is known to be increasing annually.

Also in 2013, CATT researchers Dr. Knight, Dr. Younis and Jason Johnson were awarded an Ontario Centre of Excellence and Natural Science Engineering Research Council grant for a “Novel Water Technology for Liveable Communities.” Under this grant the researchers are working with Envirologics to advance the “Tomahawk” waterless water-pipe cleaning technology, and to develop a new way to apply a water barrier coating to in situ water pipes.

This technology offers significant cost savings to water utilities for renovation and upgrades while at the same time allowing same day return to service.

Another area of research is water infrastructure asset management where Dr. Knight, Dr. Andre Unger, Dr. Carl Haas and their team of graduate student have been developing a system dynamics asset management tool with their industry partner cities of Waterloo, Cambridge and Niagara Falls.

To better understand the state of the trenchless industry CATT developed and conducted the first Canadian Annual Municipal Infrastructure Survey in 2013. The survey collected information from Canadian municipalities on construction renewal, financing of water, wastewater and stormwater pipelines. A total of 124 municipalities from several provinces participated.

The 2014 Trenchless Technology Roadshow in Niagara Falls featured over 60 exhibitors and 400 attendees. Click to enlarge.
The 2014 Trenchless Technology Roadshow in Niagara Falls featured over 60 exhibitors and 400 attendees.
Click to enlarge.

The survey received input from larger, medium and smaller sized municipalities. Approximately 20% of the municipal participants have a population greater than 500,000, 23% have a population between 500,000 and 100,000, and 57% have a population less than 50,000. While staff training was noted by about 50% of the respondents to be very important, 40% of the respondents reported a training budget of less than $5,000. Respondents noted that open-cut construction methods are still the dominant method for water and wastewater pipeline renewal and construction.

Critical issues identified by the survey included:

  • Improving water quality and flows, ensuring pipe integrity, and reducing water main leaks and breaks.
  • Inflow/infiltration, flow capacity and root intrusion in wastewater pipelines.
  • Flow capacity, surcharging, pipe collapse and infiltration in stormwater pipelines.

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By Cliff Holland and Charles Ross

Lightweight and highly maneuverable kayaks are becoming increasingly popular as vehicles to deal with spills of hazardous chemicals and petroleum products.

“We’re familiar with kayaks being used for all sorts of recreation,” said Cliff Holland, environmental director of Spill Management Inc. “But we’re still not used to thinking of them as a serious working vessel that can play a big part in averting an environmental tragedy from a chemical spill.”

Holland’s firm has provided site-specific and product-specific response training for 25 years to a wide range of clients, including mining and forestry interests, industry and the military, where potential spills to waterways are a major concern, particularly in remote areas.

“When we design training programs, one of our focuses is on selecting supplies and equipment that have multiple and diversified applications and are appropriate for the site and potential problems,” said Holland. “When response time is a critical factor, you can’t always count on having everything you would like on hand, particularly when you’re away from urban areas.”

As response teams must be able to improvise spill control measures in a variety of weather and terrain conditions and site accessibility, kayaks can be a big help in spill response.

Holland is familiar with the challenges of dealing with spills on water. He has used small watercraft and inflatable dinghies for cleanups in boat slips and along shorelines for a number of years.

Ten years ago, Holland decided that much smaller craft were a better choice for a variety of spill response training. The composite hulls of Pelican kayaks were compatible with the chemicals they would come in contact with. The low-profile watercraft is stable for trainees and can be easily stored in a hazmat trailer.
Spill Management now has three kayaks, for emergency plans and for training. They were recently used in site-specific training programs for a mining company in northern Ontario and a pipeline company in the Canadian Rockies.

One unit is used for water sampling, reconnaissance, inspecting areas for boom deployment and evaluating changing conditions on the water. A second is used for moving supplies and equipment to various staging areas, as well as spill cleanup and recovery and shoreline cleanup. The third is a two-person unit that is used to help concentrate spills in calm water and for boom deployment and recovery.

The craft can easily be stored in a large trailer and are very light and easy to move so that they can be deployed in minutes. If conditions are too rough to use a kayak, they are too rough to slow, divert, contain and recover oil spill products. Responders may have to move downstream from a spill to find tranquil waters, such as a pond or lake, where large boats may not be a good choice.

“At a hydro generation dam in northern Ontario, we had a kayak working with two power boats during a training exercise to recover a spill. The kayak was able to go into shallow water along the shoreline where the power boats couldn’t go,” said Holland. “During the exercise the large powerboat was blown into the spill holding area as it tried to maneuver in shallow, rocky water. In real life, this could have resulted in the spilled material once again being released.”

Spill Management has also used a kayak as a sled to transport supplies and equipment to a spill site. It actually performed better than a sled as the shape of its hull prevented it from digging into the ground and helped to maintain side-to-side stability. Once at the site, the kayak could be used on the water, or it could be used to transport injured personnel back to where they could receive medical assistance.

During training at a pipeline company, a kayak was used for secondary containment to catch a transportation spill. While the training spill was only water, it could have been a vehicle fuel tank that was leaking or an oil drum being transported.

These lightweight and easily maneuverable kayaks allow responders to quickly deploy booms on a body of water, since they are very maneuverable and unsinkable. The ease of using a kayak means that booms can be quickly placed to contain a spill and make recovery easier.

“We’ve got to look at innovative ways of meeting our environmental protection challenges,” said Holland. “If something like a kayak can work well in training, it is going to work well in the real world. I believe that kayaks can play bigger and bigger roles in spill response on water because they are light and easy to transport, versatile and often very reasonably priced.”

For more information visit: www.spillmanagement.ca. This article appeared in ES&E’s January/February 2015 issue.

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The Almonte Lower Falls Generating Station under construction.

With a history that dates back over a century in Ontario, it would be easy to assume that the state of science and knowledge in waterpower development reached its apex some time ago. While it is certainly true that the sector is mature in its approach to the consideration and incorporation of social, environmental and economic values, there is always new information to be brought to future projects.

The Ontario Waterpower Association (OWA) is undergoing collaborative efforts to develop Best Management Practices (BMPs). Building on the creation and implementation of the 2008 Class Environmental Assessment for Waterpower, the OWA has sought to continuously improve the advice provided to proponents, regulators and other interests.

Species at risk

The OWA’s Best Management Practices explore the connection between waterpower facility development with respect to wetlands and migratory birds. Photo by Rick Robb ©Ducks Unlimited Canada. Click to enlarge.
The OWA’s Best Management Practices explore the connection between waterpower facility development with respect to wetlands and migratory birds. Photo taken by Bill Kendall. Flickr.

The OWA’s BMPs initially focused on species at risk, including lake sturgeon, American eel and channel darter.

Species at risk BMPs specifically address the relationship between waterpower projects and a particular species and offer practical advice using science-based information. A common theme in these documents is the “pathways of effects” approach to the identification of potential impacts and appropriate mitigation strategies. In all cases, the BMPs are designed to inform decision making and act to supplement professional judgement.

The OWA has subsequently expanded its efforts to develop a series of 38 BMPs associated with facility construction. These provide practical and current best practices that assist proponents and contractors in determining how to construct, rehabilitate or repair a waterpower facility in an environmentally responsible manner.

Facility construction

The Almonte Lower Falls Generating Station under construction. Photo by Rick Robb ©Ducks Unlimited Canada. Click to enlarge
The Almonte Lower Falls Generating Station under construction.

The BMPs have also been designed so that an entire BMP or portions of it can be easily incorporated into project tender documents. Professionals working on waterpower construction sites, including contractors, inspectors and contract administrators will also find this compendium useful as a reference document. Agency personnel involved in waterpower project design, review and permitting can also use them to help in the execution of their mandates.

Once again in partnership with key organizations, the Association has added three new products to the series in 2014, with a focus on wetlands, migratory birds and water quality.

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waste processing facility rendering
Typical dry source segregated organic waste processing installation. Click to enlarge.

By Christian Cabral

There is currently a strong movement in North America to prevent landfill disposal of organic waste. As a result, many municipalities and private companies are seeking diversion solutions to comply with bans and avoid financial penalties. In each case, the solution must address specific social, economic and environmental aspects. To add to the challenge, alternatives must be projected 30 to 50 years in the future. This requires consideration of future environmental policy, economic context, energy values, carbon footprints and nutrient management.

If energy recovery is part of the organics recycling strategy, two well-proven routes are available: thermal processes and anaerobic digestion (AD). This article will explore the benefits of continuous, plug-flow, dry or high solids AD as an appropriate solution for many Canadian cities.

To digest or not to digest

There are good reasons for the municipal and private sector to look at AD of municipal organic waste:

1. Power companies are increasingly looking to diversify their offerings, accommodating clean energy as part of their portfolio.

2. Anaerobic digestion can significantly help downstream composting platforms by minimizing maturation time, increasing capacity, controlling odour and wildlife nuisances and preventing pathogen vectors.

3. Provinces are looking at biogas to help offset fossil fuel demands.

4. Organics landfill bans prevent raw organic waste from disposal in landfill cells. However, stabilized residual organics, in certain cases, may be used as landfill cover after AD and/or composting.

Depending on feedstock quality, processing organic waste can be challenging. Starting at waste containers, there are two basic avenues to recycle organic waste:

•Collection of source segregated organic waste (SSO), followed by treatment at a composting site or energy producing AD plant or combination of the two.

• Collection of mixed municipal solid waste including organic wastes, followed by mechanical separation of any recyclables at a mechanicalbiological treatment (MBT) plant. The organic fraction of municipal solid waste is then either composted, or anaerobically digested for energy production.

Both organic recycling avenues have their strengths and weaknesses. While source segregated collection requires high participation rates and separate collection and transport logistics, the resulting organic waste stream is typically “clean.” This means it contains a limited amount of impurities such as plastics, glass, metals and debris. Therefore, it is possible to produce higher quality fertilizer products with greater reuse potential.

For MBT plants, waste producers have it easy and no additional collection and transport logistics are required. However, substantial technical efforts are required at the sorting plant. This leads to far more impurities that “spoil” the subsequent treatment process and typically require additional post-treatment to satisfy regulators and users. The optimum route depends on the waste source and ease of separation.

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Local children playing in the new well dug by Living Water’s volunteers and Little Beaver’s Lone Star Rig. Click to enlarge

By Joe Haynes

Local children playing in the new well dug by Living Water’s volunteers and Little Beaver’s Lone Star Rig. Click to enlarge
Local children playing in the new well dug by Living Water’s volunteers and Little Beaver’s Lone Star Rig.
Click to enlarge

Central America sits along the eastern rim of the Pacific Ring of Fire, which creates unusual soil compositions. Formed through powerful earthquakes and explosive volcanoes, they range from soft clays in Guatemala’s coastal region to super dense volcanic rock in El Salvador.

These conditions create very fertile overburden for agriculture production, which is the primary income source for the remote communities, but also is a major source of surface water pollution. For drilling crews, the overburden hides the obstacles below.

“Completing a water well is a rewarding experience for both the community and volunteers,” said Living Water International Vice President Lew Hough. “But getting to the water table can be the toughest challenge for our crews, since lightweight drills cannot pierce through dense boulders and volcanic rocks.”

Boulders and volcanic rock formations limit the organization’s drilling locations. Living Water’s eight-man drilling teams usually have the easiest drilling in Guatemala between the Sierra Madres and the Pacific Ocean. For the most part, lightweight drill rigs with mud rotary bits drill through soft overburden and pumice to access aquifers at roughly 40-foot depths. But as crews move inland, they hit a type of lava spray, a coagulation of dense volcanic material. It keeps lightweight drills from reaching target depths, and limits the area where crews can drill to within 8 – 10 miles of the coast.

With the development of heavier, more rugged drills, particularly Little Beaver’s Lone Star’s LS300 trailer-mounted hydraulic rigs, the drilling crews have been able to penetrate through the once-limiting volcanic material and access aquifers 15 – 18 miles inland. Living Water has 10 LS300 trailer-mounted rigs in Guatemala, Honduras and Nicaragua.

The El Salvador drilling crews regularly encounter hardened lava flows and situations where down-the-hole hammers can’t go any further because they encounter basketball-sized or larger boulders. The drill rig’s annular space also doesn’t move air efficiently to the hammer and reduces the crew’s progress. All of this prolongs the drilling schedule.

Normally, water well projects take a week, but when crews encounter rough conditions like those in El Salvador, progress slows because the bits require slower speeds to be efficient. This means wells can’t be completed by the time most volunteers need to leave.

The answer was a bigger, heavier drill. Little Beaver engineered the LS400T+ to handle the rough, inland terrain that plagues drilling crews in remote communities. The new drills weigh more than 31/2 tons, have a 9,000-pound push-down force and can dig to 400-foot depths, nearly 100 feet deeper than the next largest model.

Drill crews use the 9,000-pound push-down force of the LS400T+ to dig water wells for rural communities in El Salvador, Honduras and Nicaragua.  Click to enlarge
Drill crews use the 9,000-pound push-down force of the LS400T+ to dig water wells for rural communities in El Salvador, Honduras and Nicaragua.
Click to enlarge

The LS400T+ uses 10-foot long drill pipes to quickly reach target depths and can hold roughly 180 feet of 31/2 inch diameter drill pipes with its signature pipe rack.

“With the pipe rack’s capacity, Living Water’s drilling crew can easily transport their drill pipes to the next drilling location,” Little Beaver’s President Joe Haynes said.

Drilling crews train with two LS400T+ models on Guatemalan soil before trying to tackle the igneous rock formations in the surrounding countries.

Three LS400T+ units are in production and will see action in El Salvador, Honduras and Nicaragua. Honduran drill teams work more on the Caribbean side of Central America and face dense, volcanic gravel material, where stones can become too large for drag bits but not big enough for air hammers.

“The expectation is that the LS400T+ will effectively use a driver roller cone bit to drill through that hard material,” Hough says.

Each project is a collaboration of both Living Water’s in-field teams and U.S. teams.

The full-time, in-field teams work within each country, educating communities and assisting with well site selection. They ensure wells are placed away from potentially hazardous areas, such as latrines, to avoid contamination.

Site selection is a joint decision because Living Water wants the community to have the sense of ownership of the well. Hough said experience has shown that, without this, the well quickly falls into disrepair.

Living Water trains teams to use the drills and networks with other organizations and churches to recruit volunteers. At the training camps, the organization teaches people how to operate the drill, mix drilling mud and read soil formations. After camp, Living Water sends roughly six to eight teams every weekend to different drilling locations throughout Central America and the Caribbean.

The recruits are responsible for fronting the money for their trip. They may be sponsored by a church or other community organizations, such as Rotary Clubs.

Improving community life

At the beginning of 2014, Living Water expected to make 290 trips to drilling sites in Central America and Haiti. Organization’s teams and volunteers have drilled roughly 1,200 water wells with Lone Star’s drilling rigs in El Salvador, Guatemala, Honduras and Nicaragua.

Many communities rely on agriculture, such as sugar cane cultivation, as a major source of income. But aerial pesticide and fertilizer spraying runs off into major sources of drinking water, such as rivers, streams and shallow, hand-dug wells. With deeper wells, the villagers can access cleaner water and avoid ailments such as kidney failure, dysentery and amebiasis.

 

About Living WaterLivingWater_Helmet

Since 1990, Living Water International has sent thousands of volunteers to help complete more than 10,000 water projects in Central America, Africa and Haiti.

Joe Haynes is with Lone Star Drills. This article appeared in ES&E’s January/February 2015 issue.

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water pressure filter system
Delivery of the pressure filter system used to remove iron and manganese residuals.

By Allan Choi, Zoran Filinov and Marvin Fehrman

Mount Pleasant, Ontario, located in the County of Brant, is a predominantly rural-agricultural community. The County is responsible for servicing approximately 500 residences and 20 commercial accounts. Water is sourced from two existing non-GUDI (not under the direct influence of surface water) wells in individual well houses.

Iron and manganese levels occasionally exceed the Ministry of the Environment’s (MOE) aesthetic objectives. This results in brown/black sediment deposits in the reservoir and watermains, as well as taste and colour complaints from customers.

In past years, the County has dealt with iron and manganese by implementing a rigorous and regular flushing program for the distribution system. This regular maintenance not only wasted water and energy, it was also not fully effective.

In 2008, the County received a $4.3 million combination grant and loan from the Municipal Green Fund, to improve water aesthetics, water quality, and reduce water and energy waste. The total project value was approximately $8 million. This amount was divided among several smaller projects for the Mount Pleasant water supply system, namely building a new reservoir, assessing the watermains and upgrading the water facility. The new reservoir was commissioned in 2010, and the watermain assessment was completed in 2012.

A Class Environmental Assessment was initiated for the Mount Pleasant water facility in 2010 to identify a solution for elevated iron and manganese levels. It needed to be environmentally friendly, affordable, reliable, simple to operate, and meet both the short and long-term needs for the facility. Specific evaluation criteria included: water usage of the new treatment process, geotechnical conditions of the existing site, potential impacts to the natural environment during construction and operation, and life cycle cost.

water pressure filter system
Delivery of the pressure filter system used to remove iron and manganese residuals.

The preferred process involved the addition of pressure filtration and residue management processes. This consisted of a backwash equalization tank and a lagoon for iron and manganese residuals, in addition to high-lift pumping and chemical systems upgrades.

In early 2011, a local resident filed a Part II Order request with the MOE, raising concerns over the lagoon’s possible adverse environmental effects. The MOE ultimately ruled that the solution proposed is an established and approved method for municipal water treatment under the Clean Water Act. Furthermore, the MOE was satisfied that the County of Brant and R.V. Anderson Associates Ltd. developed the project in accordance with the Class EA provisions, and that a range of alternative solutions had been considered.

The design for the facility upgrades began in early 2012 and used 3D modelling/drafting to improve the County staff’s understanding of the project’s early stages. These models allowed operators to be involved during the design stage and to minimize coordination issues by providing realistic visual representations of the new equipment and building layout. This approach reduced changes and additions to the contract during construction, which frequently occurs on upgrades of existing facilities for which there is limited information.

Originally, the Mount Pleasant water facility was comprised of two ground water wells, two in-ground reservoirs, four high-lift pumps, and a sodium hypochlorite chemical dosing system for disinfection. A portable diesel generator provided standby power.

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By Erika Henderson

Despite efforts to protect public water supplies through testing, treatment and regulation, water contamination still occasionally occurs. The type and source of contamination can vary greatly, so on-site water source monitoring is recommended to help prevent contamination outbreaks.

Water is treated and tested for micro-organisms during the water treatment process, but if it is stored in a contaminated water tank, then it becomes contaminated again. Not only does the water in a storage tank need to be tested and treated regularly, the storage tank itself must also be inspected and cleaned.

Unauthorized Access

A damaged vent is one of many ways in which animals can enter a water tank.
A damaged overflow screen is one of many ways in which animals can enter a water tank.

Trespassers can cause great damage to a water tank and its contents. Therefore, it should be protected from unauthorized access. Trespassing signs, surveillance cameras, lights and a fenced in area with locks, should be installed around the perimeter of the tank. Exterior ladders should terminate 2.5 metres above the ground, with a locking ladder guard.

Other trespassers such as pathogenic micro-organisms can enter the water supply through a host. Hosts may include aquatic organisms, insects, birds and rodents, and may access the tank through openings insufficiently covered. These can

As well, a damaged vent screen is another point of entry.
As well, a damaged vent screen is another point of entry.

include: damaged vents and overflow screens, holes or gaps in the roof and shell, floor or roof

hatches that have not been properly sealed or welded. Aquatic organisms can also gain access through inlet/outlet pipes, depending on where the water comes from.

Stagnation

All tanks should be regularly monitored for mixing efficiency. However, tanks at the end of a water system, or with low filling cycles or high volumes, should be monitored more often due to their susceptibility to developing stratified or stagnated water. Stagnation occurs when water is separated into layers arranged by density from temperature, pressure and pH. The incoming water stays near the bottom and is first to exit if an over-the-top fill has not been installed. Stagnant water lures potential hosts such as flies, mosquitoes, water fleas and other insects and crustaceans, attracted to the bacterium.

Mixing systems are often installed to help prevent stratification issues by taking denser, newer water from the bottom, and mixing it with less dense, warmer surface water. Mixing systems can also help lower the carcinogenic disinfectant byproducts trihalomethanes and haloacetic acids. These byproducts are present in almost all chlorinated water supplies, but the key is to keep these levels as low as possible.

Sedimentation

water tank sediment
Pathogenic micro-organisms can find shelter and food in sediment.

Water with excess sedimentation will result in a higher turbidity reading or muddiness, and it will become cloudy when shaken or disturbed. Sedimentation can include anything from dirt particles to rust and interior coating particles. Sedimentation often accumulates on the bottom, or in the bowl of the tank. It can also accumulate inside the outlet pipe, causing obstructions and a greater rate of deterioration. Accumulation rates vary by tank, but it is important to understand that pathogenic micro-organisms find shelter and food in this excess sedimentation. The longer sediment remains in a tank, the greater the risk for contamination and pathogenic micro-organism growth.

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Thousands of commuters were stranded in Toronto on July 8, 2013 after close to 140 mm of rain fell in just a few hours. Photo by mark.watmough via Flickr, CC BY 2.0.

By Laura Zizzo, Travis Allan and Alexandra Kocherga

The rise in extreme weather events and resulting strain on municipal infrastructure has brought increased attention to stormwater management. Recent class action lawsuits related to flooding, have been brought against municipalities, conservation authorities and the Province of Ontario, demonstrating the legal risk associated with stormwater management. These class actions alleged systematic problems.

It is important for governments and other stakeholders to consider potential legal liability concerns due to increased flooding risks, and to work towards minimizing liability where possible.

Many stakeholders including municipalities, conservation authorities and provincial government, make infrastructure investments, management decisions and operational policies that have a direct impact on the safe and effective management of stormwater. In the absence of a clear set of best practices and standards, many have important unanswered questions about the appropriate level of service that should be provided. This uncertainty is enhanced by increased municipal development and climate change, which may create new costs and technical challenges for existing systems. In some cases, the scientific and technical foundations upon which management decisions are being made may no longer be valid, due to development and climate change influences. Failing to account for these could lead to unanticipated, or unacknowledged, decreases in service levels.

It is not only governmental authorities that need to be aware of legal risks. Contractors, private landowners and residents all have roles to play in the management of stormwater and potential legal liability. A better understanding of potential legal liabilities can assist those involved in stormwater management to ensure thoughtful and diligent management practices.

Beware of negligence

Legal obligations related to stormwater management are determined by both legislation and common law, which is judge made law determined through the courts. Legal changes in Ontario and some other jurisdictions mean that common law causes of action against municipalities relating to flooding, are primarily grounded in negligence.

In establishing negligence, a plaintiff must show, on balance, that the defendant owed them a duty, breached the applicable standard of care, caused the harm and could reasonably have foreseen the injury. These tests are determined on a case-by-case basis and could be impacted by climate change and other considerations.

A recently launched and subsequently withdrawn class action in Illinois, invited a court to consider whether municipalities were negligent in preparing for severe rainstorms in light of climate change. This action may signal the beginning of explicit references to climate change in these types of cases.

Governmental policies vs. operations

Since governments have to make tough decisions about budgeting resources and balancing priorities in the public interest, courts are reluctant to find negligence with respect to policy decisions. Courts generally see policy decisions as part of the democratic process, and defer to the judgment of elected officials. However, not all decisions are exempt. The courts have acknowledged that “operational” decisions, actions and inactions, can be subject to judicial scrutiny for negligence claims.

In order for a decision to qualify as “policy,” the decision maker must have specifically considered the issue at hand and made a conscious decision to act, or not to act, based on social, political and economic factors. Simply failing to consider an issue is unlikely to be considered a policy decision. An operational decision, by contrast, relates to how a municipality executes, or carries out, a given policy decision.

Governmental authorities can be held liable for flooding damage that results from a negligent operational decision. Changing information, including that related to climate change, could increase the number and size of lawsuits. For example, residents receiving stormwater management services are owed a duty. They may become more vulnerable, particularly if avoidable potential impacts of climate change are reasonably foreseeable. A valid policy decision, as opposed to an operational decision, can negate a finding that a duty of care exists and prevent a finding of negligence.

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For water quality technicians, employers are looking for workers who can combine hands-on, field sampling skills gained from a technical school or direct work experience, with the analytical skills typically gained through a bachelor’s degree program. Click to enlarge.

By Jennifer Schultz

Careers in water quality are not just in high demand, they are also undergoing rapid changes. Climate change, population growth and urbanization create new challenges that professionals must address to reduce negative impacts on water resources. To determine the current status and future growth of Canada’s water quality workforce, Environmental Careers Organization (ECO) Canada conducted a recent study, titled Careers in Water Quality.

Current demand

In 2013, Canada had an estimated 1.8 million workers who used environmental skills as part of their work activities. Some 500,000 apply water quality skills in their work, while roughly 83,500 professionals work in core water quality careers. While most industries have a demand for water quality practitioners, the three most likely to hire water quality practitioners are government, consulting firms and water utilities.

Educational requirements,
skills and competencies

The water quality job market is shifting to higher educational requirements. Nearly 75% of new job openings in water quality require a bachelor’s degree. However, only 25% of the water quality labour force has one. Across most water quality occupations, water quality practitioners require similar environmental skills and competencies such as:

  • Analyzing or interpreting environmental samples and data.
  • Liaising and partnering with stakeholders.
  • Presenting expert information on environmental matters.
  • Developing sustainable development indicators, plans or strategies, and implementing or monitoring sustainable development strategies or programs.
  • Conducting environmental assessments.
  • Developing or implementing environmental communications and awareness programs.

Water career options and salaries

Research shows that most water quality jobs involve eight broad practice areas:

  • Integrated water resources and watershed management.
  • Protection of groundwater from contamination.
  • Protection of surface water.
  • Marine water quality.
  • Aquaculture and food processing.
  • Municipal water systems, including water treatment, water distribution, wastewater treatment and wastewater collection.
  • Green building.
  • Water quality education, communication, policy and planning.

Career pathways

Water resources engineers, water quality scientists, and professionals in water quality communications, education, policy and planning often begin with a bachelor’s degree. For water quality technicians, it is at least a three-year diploma.

Typically, the listed professionals make lateral career moves between different types of roles and employers, such as NGOs, governments, private industry, or consulting.

Engineers, water systems operators, and green building professionals, follow more vertical career pathways. These workers progress from entry-level to senior level positions and through progressive management roles.

Municipal water systems operators follow a more narrowly defined career path through four classes of certification. Based on their certification level and experience, these practitioners move up into system supervisor, operations manager, or facility manager positions.

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The Peterborough WWTP. (1) Raw sewage pumping station. (2) Grit tanks. (3) Screen building. (4) Primary clarifiers. (5) Secondary treatment Plant One. (6) Secondary treatment Plant Two. (7) UV disinfection. (8) Digesters. Click to enlarge.

By Valera Saknenko, Vincent Nazareth, Roberson Gibb, Patrick Devlin and Krista Thomas 

The Peterborough Wastewater Treatment Plant (WWTP) in southern Ontario is a Class IV plant discharging to the Otonabee River. As a result of municipal growth, average capacity had to be increased from 60,000 m³/day to 68,200 m³/day, with a simultaneous improvement in effluent quality.

This plant re-rating was achieved by full conversion of the existing aeration tanks to a hybrid integrated fixed film activated sludge (IFAS) media system. Concurrent upgrades included improvements to the inlet works, construction of four new primary clarifiers, a sludge dewatering facility and a new septage receiving station.

The Peterborough WWTP. (1) Raw sewage pumping station. (2) Grit tanks. (3) Screen building. (4) Primary clarifiers. (5) Secondary treatment Plant One. (6) Secondary treatment Plant Two. (7) UV disinfection. (8) Digesters. Click to enlarge.
The Peterborough WWTP. (1) Raw sewage pumping station. (2) Grit tanks. (3) Screen building. (4) Primary clarifiers. (5) Secondary treatment Plant One. (6) Secondary treatment Plant Two. (7) UV disinfection. (8) Digesters.

Since September 2011, it has been operating as an IFAS plant, resulting in a number of process benefits, including lower average total ammonia nitrogen (TAN), non-toxic effluent, and greater resiliency of the nitrification process to both organic and hydraulic shock loads.

Nitrogen transformation

To effectively evaluate the impacts of the IFAS system, it is important to first revisit some chemistry theory to appreciate the transformation process that occurs inside one.

The majority of nitrogen enters wastewater in the form of urea and fecal matter, and is then converted through hydrolysis to TAN. TAN (or more correctly TAN-N, which measures only the mass of nitrogen) is the sum of two molecules: NH3 (ammonia or un-ionized ammonia) and NH4 (ammonium or ionized ammonia). In essentially all solutions, including wastewater, both the ionized (NH4) and un-ionized (NH3) forms are present due to the principles of acid dissociation.

The un-ionized form is the compound that is most toxic to fish. Fortunately, for aquatic species, at pH levels in typical wastewater, NH4 is present in much greater concentrations than NH3 (100:1 ratio at pH of 7.4). However, the NH³ percentage rises with increasing pH and/or sewage temperature. This means that, for identical TAN measurements, warmer effluent results in greater toxicity due to the higher NH3 levels.

To limit un-ionized ammonia effluent concentration, TAN must be reduced through a two-step bacteriological conversion process (known as nitrification) during secondary treatment. Ammonia is first converted to nitrite (N02) using Nitrosomonas bacteria. Subsequently, the nitrite is converted to nitrate using Nitrobacter bacteria. The first process (conversion to nitrite) is the rate limiting process, meaning that nitrate is usually present in much greater concentrations. For aquatic species, the rate limiting reaction is critical, since nitrite is toxic at significantly lower concentrations.

nitrogen components
Common nitrogen components in wastewater