The Value of Unidirectional Flushing

In layman’s terms, unidirectional flushing is water flowing in one direction: a one way traffic lane for your local water distribution system. And the process is, for the most part, as simple as that.

To elaborate a bit more, unidirectional flushing, otherwise known as UDF, is an annual process used to aid and maintain water distribution systems like the one in your local area that provides your drinking water. We at Tata & Howard designed UDF programs specifically to remove unwanted tastes, odors, and discoloration in a water supply, to flush out bacteria and tuberculation that has built up, prolong the life of pipes and hydrants, allow for technicians to locate broken valves and hydrants, and to further pinpoint other water quality and supply issues.

Bye, Bye, Bacteria

What does flushing water in one direction have anything to do with preventing water-borne disease? For starters, let’s examine the diagram below of a water distribution system that utilizes conventional flushing.

As shown in the diagram, clean water is flowing from the tank into the water distribution system but is met with the free-flowing sediment and rust-mixed water from every direction. The direction in which the water flushes is crucial because the one-way water flow keeps the tainted water separate from the clean water, unlike the conventional flushing pictured above. With this method, sediment, microbial bacteria, corrosion, etc. are not circulated in the clean water, therefore preventing it from making into your next glass of water.

Since tainted water isn’t being fully flushed out in conventional flushing, sediment, rust, and microbial bacteria are building up within some of the pipe’s walls. This build up, or tuberculation, can negatively affect how much water can be distributed.

Under Pressure (Washing)

A great component of UDF is that the water is flushed throughout the distribution system at a higher velocity. If the water rushing down these pipes is at a higher velocity, that means tuberculation that has built up in the pipe’s walls will wash away, too. Picture it like your water distribution system’s very own water pressure system, blasting away microbial and rust buildup, and tossing it out with the rest of the bath water.

In Municipal and Sewer and Water Magazine, Shrewsbury, MA water and sewer superintendent — and Tata & Howard client — Dan Rowley states that when fire hydrants are opened to increase the water velocity, it “increases to 5 to 10 feet per second, compared to 1 to 3 feet per second in conventional flushing.” With that kind of power, tuberculation doesn’t stand a chance.

Now, when some people think of ramping up the speed dial on something, they think more power equals more resources, but that’s not the case here. UDF uses upwards of 40% less water than conventional flushing. A higher population to serve brings a higher water demand, which leads to a lower supply due to demand and climate change. All of this then results in a crucial need to seek out the most cost-effective and sustainable methods in order to maintain, improve, and prolong our planet’s natural resources. And UDF does just that.

Improve System Performance

During the unidirectional flushing process, valves are opened and closed to maintain a unidirectional flow.  In the process, broken and closed valves as well as nonfunctioning hydrants are identified. Not only are you cleaning the water pipes during the UDF process, you are also identifying critical system components such as valves and hydrants that need replacement or maintainance.

Regardless, any water distribution system needs flushing. So why not perform it in such a way that you can simultaneously flush our tuberculation and bacteria from your pipes’ walls, prolong the quality of your valves, hydrants and pipes, use less water, and also improve overall water quality and quantity issues? This is one of those win-win situations!

At Tata & Howard, our UDF programs are implemented all over Massachusetts, ranging from Shrewsbury to Wayland, and Melrose to Haverhill, and down to parts of Connecticut. By adopting one of our UDF programs, a water distribution system can maintain efficiency and cleanliness longer between flushes, save money, and ultimately use less of our earth’s natural resources.

Tata & Howard Announces Co-Founder’s Retirement

Paul Howard set to retire from the Massachusetts-based environmental engineering firm at the end of the year

Tata & Howard, Inc. has announced the retirement of Tata & Howard Co-Founder and Senior Vice President Paul Howard as of December 31, 2022. While he is stepping down from day-to-day operations, Mr. Howard will remain on the Board of Directors and serve as a technical advisor to the current leadership team led by Karen Gracey, P.E. and Jenna Rzasa, P.E., who were named Co-Presidents in 2017.

“Tata & Howard’s succession plan was underway when the company became a 100% ESOP in 2014,” commented Ms. Rzasa. “While Paul was originally planning to retire years ago, he graciously remained on the team to assist during the leadership transition that was expedited due to the untimely death of our firm’s President Don Tata.”

Donald Tata and Paul Howard co-founded Tata & Howard in 1992 and grew the firm from a two-person start-up to a highly successful engineering firm with multiple offices throughout New England and Arizona. In 2014, Mr. Tata and Mr. Howard created a 100% ESOP for Tata & Howard and lined up Ms. Gracey and Ms. Rzasa to assume leadership while they transitioned to retirement. However, in 2017, Mr. Tata passed away after a short illness. At that time, Mr. Howard resumed a full-time role with the company to assist the newly appointed Co-Presidents with the transition. Now five years later, Mr. Howard is looking forward to retirement.

Gracey and Rzasa have been with the firm since 1998 and 1997, respectively, and were named to the Board of Directors in 2013. As Co-Presidents, they have focused on Tata & Howard’s strategic plan while adhering to the firm’s core values and mission of providing unsurpassed solutions in the water environment. Vice Presidents Justine Carroll, P.E., Ryan Neyland, P.E., and Jon Gregory, P.E., who have a combined 50 years of experience with the firm, will continue to provide strategic and operational support to Gracey and Rzasa.

“Since the firm’s inception, Paul has served as a pillar of innovation, integrity, and technical excellence to Tata & Howard,” added Ms. Gracey. “While we will miss him in the daily operations of the firm, we are grateful for his unwavering support over the past five years and are looking forward to his continued thought leadership as part of the Board.”

Mr. Howard received his B.S. in Engineering from Worcester Polytechnic Institute where he met Mr. Tata. Mr. Howard’s career has included numerous success stories including the design and construction of the Shrewsbury, MA Home Farm Water Treatment Facility, which at time of construction was the second largest biological treatment facility in the country, and which received the prestigious 2020 Bronze Award for Engineering Excellence through ACEC. Additionally, Mr. Howard served as Project Manager for the design and construction of the Town of Natick’s water treatment facility, which was the first to recycle backwash water in the Commonwealth of Massachusetts. He has served as President of the Massachusetts Water Works Association and has been involved in many trade committees including legislative, technical, awards, finance, and nominating. Mr. Howard was the recipient of the 2009 Past President’s Award, 2011 William H. McGinness Award, 2016 Water Works State Leadership Award, and the 2018 Executive Director Award. He is also a lifetime member of the American Water Works Association.

See photos from his retirement party here.

Project Engineer, Water Engineering – Marlborough, MA

Job Description:

We are looking for a qualified and highly motivated Project Engineer, Water Engineering with 4-7 years’ experience in water distribution engineering to join our Marlborough office. The selected candidate will work directly with our clients and a team of design engineers in a variety of civil engineering projects including pipelines, pump stations, and water treatment. The successful candidate will have a proven record of meeting project deadlines and budgets. Other responsibilities include mentoring and training junior engineers, coordinating / participating in the preparation of plans and specifications, technical report writing, and documenting project activities, findings, and recommendations, with limited supervision. The candidate must be a self-starter with a solid understanding of the consulting engineering industry. Familiarity with Deltek Vantagepoint project management system a plus.


  • Bachelor’s degree in Civil or Environmental Engineering.
  • 4-7 years of experience in the consulting engineering industry involving the design of municipal water systems.
  • Registered Professional Civil Engineer in the State of Massachusetts or the ability to obtain through reciprocity.
  • Previous experience working on and managing projects for municipal water clients.
  • Proven history of developing and managing projects from design through construction.
  • Candidate must have strong technical skills.
  • Strong written and verbal communication, organizational and interpersonal skills.
  • Candidate must be able to work well independently and in teams and manage multiple projects simultaneously.

Please note that Tata & Howard does not sponsor applicants for work visas.