Scaling UP! H2O

355 Backflow Prevention: Safeguarding Water Quality

“Why is the water weirdly blue? Why does it smell bad? Why does it taste bad? The culprit is frequently Backflow.” – Kalpna Solanki

Delve into the mysteries behind strange-tinted water, unpleasant odors, and off-putting tastes – all signs pointing to an all too common culprit: Backflow. Uncover the shocking narrative of over 50,000 residents enduring weeks without water due to industrial chemicals infiltrating their drinking supply in Ontario, Canada. Join Kalpna Solanki, President and CEO of the Environmental Operators Certification Program, on a mission to safeguard our drinking water.

In this episode, Kalpna Solanki delves into the concealed dangers of Backflow, the inadvertent reverse flow of harmful substances into water systems. Through gripping case studies, she paints a vivid picture of the potential consequences of backflow incidents, emphasizing the critical need for proactive prevention measures. Kalpna shares insights on emergency response teams, navigating legislative challenges, and the ongoing commitment to professional development in ensuring water safety.

Immerse yourself in the latest Scaling UP! H2O episode, where Kalpna Solanki, as a water quality advocate, exposes the unseen threat jeopardizing our drinking water – Backflow. As the dynamic leader of the Environmental Operators Certification Program, Kalpna narrates real stories from the front lines of water treatment, underscoring the paramount importance of backflow prevention.


Episode Highlights:

Backflow Unveiled:
Kalpna guides listeners through the unexpected dangers of Backflow, shedding light on instances where the safety of our water supply teeters on the brink. Explore the indispensable role of Backflow prevention devices and the unsung heroes, Environmental Operators, dedicated to ensuring these guardians of clean water fulfill their duty.

Importance of Emergency Response Teams:
Kalpna discusses the need for emergency response teams to address issues related to extreme weather events and climate change. Highlighting the importance of contingency plans and teams in industrial water treatment facilities, she provides insights on working with legislators to formulate a plan before disaster strikes.

In the Trenches: Real Backflow Incidents:
Listeners will be captivated by narratives of actual Backflow incidents, where the absence of prevention measures led to contamination crises – stories that underscore the urgency of our collective responsibility.

A Path Forward:
Kalpna and her team have developed resources to help water professionals learn about Backflow, partner with local legislation to improve public drinking water, and enhance safety through education, maintenance, and laws.

Kalpna’s passion for water quality and preventing water disasters is contagious, and these stories resonate with the heart of every water professional and concerned citizen. Join the episode to become part of the solution, unveiling the hidden threats to our most precious resource. Tune in now to Scaling UP! H2O and stand as a defender of clean water!



01:00-  Upcoming Events for Water Treatment Professionals

09:00- Interview with Kalpna Solanki

46:10 – Lightning Round Questions

56:00 – Drop by Drop With James McDonald 



“This industry is recession-proof. There will always be a need for environmental operators. It’s a career with lots of opportunities. You can work anywhere because everyone needs people to take care of drinking water and wastewater management.” – Kalpna Solanki

“Knowledge is never wasted.” – Kalpna Solanki

“You are putting the public’s health at risk when you don’t have the proper systems in place.” – Kalpna Solanki

I would love people to find out about Backflow, what exactly it is, why it’s important, and why lawmakers should be paying more attention to this so that we don’t have these incidents of people accidentally, literally, being poisoned via their drinking water because it is completely preventable. That’s the thing about it. It is completely preventable, and it’s not a big ticket item.” – Kalpna Solanki

“There’s a finite amount of water on this planet, and we really need to spend a bit more time looking at not just water conservation, but water treatment, water reuse and the circular water economy.” – Kalpna Solanki


Connect with Kalpna Solanki

Phone: 778.688.9196



Water Environment Federation (WEF)

LinkedIn: in/kalpnasolanki


Read or Download Kalpna Solanki’s Press Release HERE


Links Mentioned

Join Team Scaling UP! Nation’s Global 6K on May 18th

British Columbia Institute of Technology for Water and Wastewater Operations

Read Kalpna’s Publications on Operator Digest Magazine

Become a #watergeek – What is an Environmental Operator and what do they do?

Water Environment Federation (WEF)

Examples of Backflow Incidents in Canada

2021 Floods in Merritt, B.C.: Review and Repair

Cleaning Up Edmonton’s Sewer Smell

Ontario Canada Petrochemicals 50,000 Residents Impacted from Backflow

The Rising Tide Mastermind

Scaling UP! H2O Academy video courses

Legionella Resources Page


Books Mentioned

Lessons In Chemistry by Bonnie Garmus

How Will You Measure Your Life? by Clayton M. Christensen

The Big Necessity: The Unmentionable World of Human Waste and Why It Matters by Rose George

Reverse Osmosis:  A Practical Guide for Industrial Users by Wes Byrne


2024 Events for Water Professionals

Check out our Scaling UP! H2O Events Calendar where we’ve listed every event Water Treaters should be aware of by clicking HERE or using the dropdown menu.


Drop By Drop with James

In this week’s episode, we’re thinking about reverse osmosis. In particular, we are thinking about the dissolved solids and some of the things that influence their passage through the RO membrane. More than simply filtration, reverse osmosis is a diffusion process through a semipermeable polymer membrane. That sounds fancy, I know, but it can be more than simply size that matters for dissolved solids trying to pass through the RO membrane.   

One of my go-to books for RO is written by Wes Byrne and is called “Reverse Osmosis:  A Practical Guide for Industrial Users,” 2nd edition. I have not read it cover to cover, but drop by drop as I have questions or needs. It’s a good, well-written, practical book that makes a complex subject digestible.   

Right in the very beginning, it sneaks in some important concepts, on pages 8 through 14 in particular, that opened my eyes more as I thought about them. First, it talks about the size versus apparent size of atoms and molecules trying to pass through the RO membrane. When you think of sodium or calcium atoms, you probably think of just a single sodium or calcium atom floating around the water solution. However, as we learned in last week’s episode of Drop by Drop, we know water molecules are sticky because of hydrogen bonding. Sodium and calcium are charged ions, and they will be surrounded by water molecules hydrogen bonding to them, making an ion group with a larger apparent size. Did you hear that? The apparent size of the sodium and calcium ions are bigger than their individual sizes because of the entourage of water molecules attracted to them. This is called ion hydration. The higher the charge of the ion, the greater the number of water molecules attracted to it, and the more difficult it is for it to diffuse through an RO membrane.   

Now, before I had read this part of the book, I had heard that the higher the ionic charge the higher the percent rejection typically was, but I had never considered the role that water’s hydrogen bonding played in that rejection. That’s one more reason to love hydrogen bonding. 

I’m not done yet, however. A second concept that this book drove home for me can be found on page 9. It mentions that the water solutions we commonly deal with are neutrally charged with no charge imbalances overall. Sure, there are positively charged cations and negatively charged anions, but they will tend to stay close together, resulting in a net neutral charge. This also means that you will not have a cation passing through an RO membrane unless an anion or anions of EQUAL charge quantity passes through as well. Your plusses must equal your minuses of what passes through. 

Woah!  Now not only do dissolved solids have a larger “apparent” size because of ion hydration, but there is a balancing act of what can pass through an RO membrane based upon their charges as well? Yes, and it is FASCINATING! The example given is of sodium sulfate or Na2SO4. When it dissolves in water, we will have sodium ions with a +1 charge and sulfate ions with a -2 charge. They’ll both be surrounded by water molecules making their apparent sizes bigger. The sulfate ion with its larger -2 charge will have an even larger apparent size than the sodium ion, so the sulfate will have a much harder time getting through the RO membrane. One would think the sodium ion, with only its +1 charge, might sail on through, but hold your horses. Because the total charges of what passes through the membrane must balance out, if the sulfate can’t go, then the sodium won’t go either. Now that’s loyalty!  However, if we add some calcium chloride or CaCl2 to the water, things change. Now you have positively charged calcium ions with their +2 charge and negatively charged chloride ions with their -1 charge. Chloride’s -1 charge is smaller than sulfates -2 charge, so its apparent size will also be smaller, and it will more readily pass through the RO membrane. Now, the charges passing through the membrane will be balanced as both sodium (+1) and chloride (-1) pass through as calcium and sulfate stay behind.  The entire dynamic changed! 

Man! That’s a lot!  I hope I made it somewhat understandable and did the topic justice. You might have to rewind to listen again because this water’s deep. I’ve just had these bits of RO information rattling around in my brain for years and have seen many “Aha” moments when sharing them with others.


Water Treatment education

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