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First neighbourhood-scale study of home water pumps shows that they decrease water pressure moderately, but have minimal effect on average water quality 

With utilities in countries such as India running water infrastructure intermittently to minimize water lost to leaky pipes, many residents use pumps to draw as much water as they can when it is available (photo by Noah Seelam/AFP via Getty Images)

Household water pumps are a quirky feature of many urban water systems around the world. Utility operators hate them, and in many places they have been made illegal, yet their use remains widespread. A new study authored by Professor David Meyer (CivMin, CGEN) looks at how these pumps affect water quality — and it contains some surprises. 

“Because the use of these pumps is often illegal, they haven’t been well studied,” says Meyer. “But this is not a problem that’s going away. I estimate that there are probably 250 million people around the world that drink water that is pulled out of water pipe systems by these pumps.” 

In North America, household water pumps are typically only used by people who get their water from wells or from a nearby lake or stream. By contrast, city dwellers rely on their public utilities to deliver water under high enough pressure so that when they open the tap, the water flows. 

But in many places around the world, that’s not the case. Meyer (né Taylor) and his team study intermittent water systems, which are turned on and off several times throughout the day or week. 

While this type of operation can minimize the amount of water that is lost to leaky pipes, it also creates an incentive for customers to extract as much water as they can while it is available. 

“It’s a bit like an arms race,” says Meyer. “If the water delivered to you is at low pressure and comes out slowly, a pump connected directly to the city’s system will pull the water out faster. But that lowers the pressure for everyone else around you, which drives them to buy pumps too.” 

The study, recently published in Water Research X, was carried out in Delhi, India. Meyer says that in parts of that city, it’s possible to tell when the water system is about to be activated simply by listening for the humming sound produced by hundreds of household water pumps switching on.  

All these pumps pulling on the pipes creates negative pressure in the system, which in turn leads to other issues. One is that people who don’t have pumps often can’t get any water, even when the system is turned on. 

Another is that the negative pressure can suck dirt, sewage or other pollutants into the water system, contaminating the supply. 

“When I started this project, officials at the local water utility told me that these pumps were their number one problem, full stop,” says Meyer. “The public utility has claimed that 90% of contamination issues can be traced to the use of these devices.”

To test this, Meyer and his collaborators came up with a simple solution: a small, low-cost (less than $20) pressure control valve that can be fitted onto any pipe to neutralize the effect of downstream pumps.

In many areas of Delhi, India, households use water pumps like these to pull water out of the pipes faster than it would otherwise flow from their local utility. A new study suggests that contrary to what is commonly believed, these pumps don’t always have a strong effect on average water quality. (Photo: David Meyer)

This simple plastic valve can be used to restrict the flow of water and neutralize the effect of a household water pump. (Image: David Meyer)

“As the pump operates, the valve automatically collapses itself to restrict the flow and keep the overall pressure the same,” he says. “Once we had this intervention, it enabled us to do a controlled experiment to find out how exactly the pumps were affecting water quality, which was something that hadn’t been done before.” 

Meyer and his team took more than 500 water quality measurements from two neighbourhoods over the course of about six weeks to get a baseline. After that, one of the two neighbourhoods was fitted with these new pressure control valves, and the team collected another set of more than 500 measurements, covering another six weeks. 

Having a pump more than doubled the chances of finding a water sample with high turbidity, a measure of the water’s cloudiness that is sometimes associated with water quality concerns. 

But on average, the water quality varied ten times more from day to day and week to week than it did between the two neighbourhoods, likely due to what was happening in the rest of the system. 

“We expected dramatic effects, but pumps actually made very little difference to average water quality,” says Meyer. 

A more substantial effect was found by studying the water pressure, which also affects water safety. The neighbourhood with pumps had an average water pressure that was lower by about 0.5 m. That’s not a lot compared to the pressure in an average North American system, but in Delhi it represents between 20 and 40% of the water pressure many homes receive, meaning a big loss for people without pumps. 

The findings come with some caveats: the study involved only two neighbourhoods with a combined total of about 500 water connections. It also took place during the dry season — in the wet season there would have been more groundwater moving near the pipes that could potentially have carried contaminants. 

Still, Meyer says that the overall results point in two interesting directions. 

“Increasing water pressure by neutralizing pumps is a good thing, because it reduces the chance that contaminants can force their way into the pipes,” he says. 

“On the other hand, we now know that, at least for this area and this time of year, pumps are not the main factor driving water quality issues. Rather than focusing on pumps, we can focus on other things, such as improving the overall system integrity through leak detection and increasing the hours per day of water supply.” 

Meyer hopes that more studies like his will be done in the future. 

“Given that 250 million people get their water using these devices, it’s astonishing to me that until now, nobody had measured what they actually do,” he says. 

“I can’t say we’ve answered all the questions, but it’s an exciting first start. Now that we’re looking into this dramatically understudied feature of many water systems around the world, I hope others will start to pay more attention to it.” 

By Tyler Irving

This story originally published by Engineering News

A message for Engineering students, faculty & staff from Engineering Dean Chris Yip

To our U of T Engineering community

More than half of the population in Canada has now received a first dose of a COVID-19 vaccine, and in Toronto, the proportion is over 70% of adults. Second doses are coming, and the Ontario government recently announced its three-phase reopening plan. As I shared in a past Dean’s message, here at U of T Engineering, we’ve also been mapping out our plans for a safe and gradual return to campus.

Our plans are being built from the latest public health guidance and government directives. Indeed, the entire University has been working diligently since the pandemic began to rethink every facet of our operations — from signage and scheduling, to ventilation and vaccination — to ensure the safety of our whole community.

Of course, there are still a lot of questions and details outstanding, but I wanted to provide the outline of our scenario planning, the rationale behind it and the considerations we have made. I know it’s a lot of information, but I am sharing this so that each of you, whether you’re an incoming first-year, returning undergrad, graduate student, staff or faculty member, can begin to imagine how the Fall Term may look for you, and have as much info as possible to make your own plans.

Our leadership team, Departments, Divisions and Institutes, the Registrar’s Office, our Faculty’s Health and Safety advisors, and the Graduate Offices are working hard to develop a schedule that will prioritize as many in-person course activities as possible, while considering student workload, travel or commute times, health and safety and well-being. We also continue to work closely with EngSoc into and throughout the summer on scenario planning for extra-curricular activities such as student teams and orientation.

Review the scenarios planned for the Fall Term:

• Undergraduate students
• Graduate students

It is crucial to remember that even if we start the term under one plan, changes in public health guidelines could mean an unpredictable switch. We need to be prepared to pivot and adapt. We advise preparing for both Plans A and B, as these are based on the current provincial health and safety guidelines, which could change. Course instructors are also working to develop in-class delivery under both plans.

My central message is this: plan to be in Toronto. I encourage those who are able to be vaccinated to get their shots, as I have. While I acknowledge the past 15 months have been a grind, and I know many of you have faced challenges in your personal, professional, academic lives and beyond, I’m also enormously energized by the prospect of seeing you on campus again this Fall Term.

 There will be bumps in the road ahead, but we’re moving forward. I will continue to keep you updated as we go.

Chris

Christopher Yip
Dean
Faculty of Applied Science & Engineering
University of Toronto

—

Scenario Plans for Fall Term in U of T Engineering

Undergraduate students

Plan A: In-Person Course Activities

• This is our “as in-person as possible” scenario, which involves in-person delivery of all course activities.
• This is our default plan.
• This plan is feasible as long as we do not have any physical distancing or significant gathering limit restrictions imposed by public health guidelines; however, we anticipate the continued use of non-medical masks indoors and outdoors while on campus.
• We hope that in this scenario, small club and student group gatherings will be possible but realize that, at this time, this cannot be guaranteed.
• When registration for U of T Engineering undergraduates opens on July 14, 2021, students will register for courses as if they will take place in person under Plan A.

Plan B: In-Person Pods, Labs & Tutorials

• The University has asked all divisions to develop a Plan B in the event that public health guidelines do not allow us to proceed with Plan A.
• U of T Engineering’s Plan B is based on a hypothesis of having the strictest public health restrictions that would still enable us to facilitate some in-person activities: gathering limits of 50, and no physical distancing requirements. We also anticipate the continued use of non-medical masks indoors and outdoors while on campus.
• Since not all course components can be in-person under Plan B, we are prioritizing those smaller in-person activities that are focused on hands-on and/or interactive experiences, which are generally the laboratories and tutorials.
• With gathering limits of 50, the numbers of tutorial and laboratory sections drastically increase. In this scenario, with the anticipation of classrooms being fully utilized (at low capacities), U of T Engineering does not have the space required to satisfy public health restrictions that would allow students to congregate, wait, study or attend synchronous online lectures between their in-person labs and tutorials.
• We also do not have the space required for students to wait and study within our buildings between course activities. We are being mindful to avoid crowded and congested spaces.
• Therefore, Plan B involves designing cohorts of undergraduate students in Years 1 and 2, divided into ‘pods’, whereby each pod’s in-person course activities (labs and tutorials) are scheduled together, so that they can leave campus when they are done their in-person activities for the day. Due to the custom nature of Years 3 and 4, we do not have a pod structure for upper-year students.
• In developing a Plan B, we are prioritizing in-person labs and tutorials over synchronous online lectures. While we understand that this is not ideal for every course, we believe this will provide students with a better overall experience, addressing their desire for in-person peer-to-peer interaction.
• Since undergraduates will be grouped into pods, we are encouraging students to come to campus only on days when they have in-person course activities.
• In this scenario, we expect that all extra-curricular activities will stay virtual. If a club or design team has a specific request or concern, they are encouraged to first coordinate with EngSoc, whom we have been working with continuously through the pandemic and into this summer.

Plan C: Remote (with some exceptions)

• If physical distancing is required, then the vast majority of in-person activities will not be feasible. We will run our Plan A schedule for undergraduate courses, but it will be fully remote with the exception that some programs will still hold some in-person laboratories.
• All extra- and co-curricular activities will also be remote under Plan C.

Graduate students

Plan A: In-Person Under 50

• If public health guidelines require little or no or physical distancing or gathering limits, for graduate courses where the class size is smaller than 50, the default plan is to be in-person as much as possible.
• We anticipate the continued use of non-medical masks indoors and outdoors while on campus.
• For courses where the class size is 50 or more, the default plan is online lectures with in-person components in small groups. For example, when possible, these could include in-person office hours scheduled in a classroom, while still offering a portion of the office hours online.
• Course enrolment opens for graduate students on August 4, 2021. Students will register in courses as if we are proceeding with Plan A.

Plan B: Remote (with some exceptions)

• If significant physical distancing and gathering limits are still in place: most classes will be delivered remotely.
• In-person course activities that are possible under public health requirements, and that can be delivered equitably for all members of the class may be held in person.

—

Quick links:

• Undergraduate student FAQs
• Graduate student FAQs
• UTogether: Your guide to summer and fall 2021 at U of T
• International student arrival
• Quarantine information for students entering Canada
• Residences and Off-campus housing
• 24/7 counselling support through My Student Support Program (My SSP)

This message originally posted by U of T Engineering

(Infographic by U of T Communications)

Download a transcript of the infographic

As it prepares for the return of students, staff, faculty and librarians this fall, the University of Toronto is taking a wide range of precautions to curtail the risk of COVID-19 transmission.

Everyone coming to campus will be required to take a self-reported health screening. Building ventilation systems are being inspected, air filters have been upgraded where necessary and air purifiers are being added to classrooms as needed. Room occupancy will be limited, as is the case with other enclosed spaces, from grocery stores to buses.

“We’re exploring every possible avenue to prepare our campuses for a successful fall term that includes in-person learning, activities and other experiences,” said Ron Saporta, chief operating officer, property services and sustainability. “As the situation evolves, we will continue to monitor public health guidance daily to ensure that our measures are up to date and are informed by evidence.”

Here are 12 ways U of T is planning for a safe return of in-person instruction this fall:

1. UCheck health screening

Before visiting campus, everyone – students, faculty, staff, librarians, researchers and even contractors – must complete a health screening. The easiest way to do this is by using the university’s online self-assessment tool, UCheck. A paper-based process is also available.

The UCheck questionnaire has been updated to reflect the latest public health guidance, takes just a few minutes to complete and can be accessed via smartphone, tablet or desktop. Submitted data is encrypted in transit and storage to protect users’ privacy.

2. Physical distancing measures

(Photo by Nick Iwanyshyn)

To help facilitate physical distancing, the university has taken steps to re-orient traffic flow in buildings by posting signage and rearranging furniture and other features to help people maintain a distance of at least two metres from one another. In some cases, chairs have been taped off and desks and other furniture have been physically separated – or removed altogether.

“Physical distancing remains an important practice to limit the spread of COVID-19,” Saporta said.

3. Scheduling changes and capacity limits

(Photo by Johnny Guatto)

U of T has also capped the number of people allowed inside rooms to help facilitate physical distancing. Some departments have adjusted schedules so that fewer people occupy the same indoor space at the same time.

Efforts will also be made to move activities such as fitness classes outdoors while weather and public health guidelines permit – a strategy that was successfully implemented last fall.

“In keeping with the latest public health guidance, we have further limited occupancy since last spring.  We will continue to monitor the guidance in this area over the summer and make adjustments as needed,” said Saporta.

4. Non-medical face masks

The university’s policy requiring non-medical masks to be worn in all indoor spaces will remain in effect. U of T’s mask policy and allowable exclusions, as well as answers to frequently asked questions about masks, can all be found on the UTogether site.

Health Canada now recommends wearing a well-fitted masks with “at least 2 layers of tightly woven fabric, such as cotton,” plus a third middle layer of filter-type fabric, such as non-woven polypropylene.

5. Enhanced cleaning and more sanitizing stations

(Photo by David Lee)

The university has installed thousands of touchless hand sanitizing stations and sanitizing wipe dispensers across the three campuses. U of T has also ramped up cleaning of common-use areas such as classrooms, libraries, washrooms and lobbies.

Staff frequently wipe down and disinfect high-touch surfaces like door handles, handrails and elevator buttons.

6. Industry-leading classroom ventilation targets

(Photo by Johnny Guatto)

Classrooms that will be used for in-person teaching across the three campuses will be equipped for six equivalent air changes per hour, the same standard applied to patient examination rooms, walk-in clinics and other health-care settings.

U of T consulted outside experts in adopting its ventilation standard.

“In the context of the pandemic, we’ve been on top of recommended COVID-19 ventilation safety measures,” said Jelena Vulovic-Basic, a senior manager, operations and maintenance at U of T Facilities & Services.

7. Upgrading building ventilation and air filtration

(Photo by Johnny Guatto)

The university continues to upgrade and monitor heating, ventilation and air conditioning (HVAC) equipment where necessary. That includes monitoring and maintaining upgraded air filters that capture a greater percentage of smaller particles and outfitting some classrooms with a local air filtration device with high-efficiency particulate air (HEPA) filters.

All building ventilation systems at U of T will continue to undergo regular maintenance to ensure air is clean and flowing into and out of buildings properly.

As an additional measure, the university plans to flush air from enclosed spaces prior to occupancy.

“We turn on the ventilation system two hours before anyone walks through the door, filling the building with clean air,” Saporta said.

8. Contact tracing through QR codes

As part of a voluntary pilot project, people entering some buildings will see posters encouraging them to use UCheck to scan a QR code located at the entrances. The scans will help with contact tracing in the event of a confirmed case of COVID-19.

“If we have an issue, Occupational Health Services can notify people directly about a potential exposure,” said Cathy Eberts, U of T’s director, enterprise applications and deputy chief information officer.

“It’s all through UCheck, so your information is encrypted and only accessible by our occupational health nurse if we need to do contract tracing.”

9. Monitoring wastewater in large residences

A pilot project is underway at U of T to monitor sewage for the virus that causes COVID-19.

Some municipalities, including Ottawa, have been using this method to detect the virus – often before those who are infected realize they are sick.

At U of T, the plan is to monitor wastewater from residences that house about 100 people or more.

“The approach here – which was successfully tested during a pilot earlier this year – is we monitor building wastewater for pre-symptomatic or asymptomatic cases of COVID-19, and if we find it then we implement our outbreak prevention protocol,” Saporta said.

10. Rapid screening for some essential staff

The university is also piloting rapid antigen testing for U of T staff whose role requires frequent face-to-face interaction with the public, such as those working in dentistry and health and wellness.

The screening program was developed by the Creative Destruction Lab – a business accelerator affiliated with the Rotman School of Management – and has been used by the likes of Air Canada and Scotiabank.

The BD Veritor System uses nasal swabs to detect SARS-CoV-2.

The test, which returns a result in as little as 15 minutes, can accurately identify the presence of the coronavirus roughly 85 per cent of the time and can accurately eliminate those who are not infected nearly 100 per cent of the time. Those who test positive will be referred for further testing.

11. Department-specific COVID-19 guidelines and tools

Rather than taking a one-size-fits-all approach, U of T is asking each department to adapt the university’s – and indeed broader public health guidelines – to its own specific circumstances.

“It’s important to contextualize general guidelines to the space where you work,” said Gina Trubiani, U of T’s director, occupational health and safety.

“How physical distancing works in caretaking may be different from how it works in a place like the Medical Sciences Building. This allows for a nimbler, more flexible response so departments can apply the general guidelines based on their circumstances.”

12. Supporting Ontario’s vaccination drive

(Photo by Nick Iwanyshyn)

U of T is supplying space and volunteers to boost the province’s vaccination efforts. Earlier this month, a vaccine clinic hosted by U of T Mississauga and run by Trillium Health Partners and Peel Public Health celebrated an important milestone: 100,000 shots in arms.

Another clinic, on the St. George campus, is operated by the University Health Network with participation from Sinai Health and U of T. And there are plans to host a third clinic at U of T Scarborough.

In all cases, the vaccinations are administered at the U of T-hosted sites following the province’s vaccine priority schedule and ethical guidelines.

“Our main goal is to do what we can to partner with our hospitals and public health to serve our communities,” Salvatore Spadafora, a physician and professor in the Temerty Faculty of Medicine who is special adviser to the president and provost on COVID-19, told U of T News.

He later said he hoped Canada’s mass immunization effort will also help the U of T community “arrive at a better, safer and less isolated place this fall.”

As for the entire 12-step plan, Spadafora said, it will evolve with the science and the public health regulations of the day – and as case counts fall and vaccinations increase.

“The university will continue to monitor the effectiveness of these programs, as well as scientific evidence and best practices and will adapt this program as warranted.”

For the latest updates visit UTogether

By Geoffrey Vendeville

This story originally published by U of T News