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By Kristin Andersen


AYER — The last thing Dave Knowlton expected to become was an entrepreneur. Founder and co-owner of Nashoba Analytical LLC, Knowlton is a scientist with an extensive background in microbiology and chemistry. He said while water testing is not the hardest lab work he’s ever done, public health concerns make it the most important.

Knowlton got into water testing 23 years ago and discovered a growing need for this untapped service industry. In 2006, Knowlton and his wife, Rachel, opened Nashoba Analytical in a small laboratory in Littleton, and their business took off. In fact, they had to move to their present location on Willow Road after demand doubled in only four years.

Their’s is a perfect pairing of talent, as Rachel’s background in business frees Dave up to handle the science. Rachel is a full partner, serving as chief office manager, writing reports and taking care of client contact. Having grown up in her family’s printing business, where her parents also worked as a husband-and-wife team, she went into corporate accounting for both small and large companies. Her experience brings a wealth of knowledge to their shared venture.

The unhurried but efficient flow of activity reflects the way Nashoba Analytical runs. A far cry from pop culture’s far-out science labs, the Knowltons cultivate a warm, welcoming atmosphere, where the mailman is on a first-name basis and clients are encouraged to come in with their questions.

“We’re a mom-and-pop business,” Rachel explained.

Having grown up on a working dairy farm in Ipswich, Knowlton got his degree in microbiology, with a chemistry minor, at Iowa State University before heading to the oil and gas fields of Texas. After experiencing the brutality of his first Houston summer, Knowlton left the Texas heat before his second year, vowing never to leave New England again.

After returning to farming for three years, he decided to use his degree and took a job with the Gillette Company in Andover.

In 1990, Knowlton entered the field of water testing, in Massachusetts. In 2006, the scientist and his wife dove into the world of business, making an unexpectedly big splash in a time when most start-up companies were struggling.

Noting that it is “imperative” that water be tested before purchasing a home, Knowlton said many private tests are done because of home sale transactions. But many property owners have their water tested for safety, if they have a question about its quality, due to odor, taste or color.

Though E. Coli is the number one worry of most customers, the most common contaminant is actually arsenic, which is naturally occurring in the bedrock of North-Central Massachusetts. The EPA tightened the standard on arsenic testing just six years ago, from 50 parts per billion to just 10. This means that homes tested before the change might have passed the old tests but could fail the current limits.

To avoid any conflict of interest, Knowlton does not provide mitigation options to customers whose water fails to meet the standards. However, he refers clients to a list of licensed water-treatment providers. Though it can be stressful to discover that one’s water is not considered safe to drink, Knowlton noted that just about any problem can be fixed.

It is also reassuring to know that after 23 years in the business, Knowlton has complete confidence that public water supplies in Massachusetts are heavily tested and safe.

Municipal and private water supplies that fail to meet mandated standards can be treated. Sometimes the cause can be due to a crumbling infrastructure. Other times, the problem lies within an individual home’s own system. For example, homes built before 1986 can contain lead in the solder of pipe joints. Even some supposedly “lead free” brass sometimes contains lead. Each situation is unique and must be treated on a case-by-case basis. The important thing is to make sure that testing is done regularly,whether one is buying a new home or continuing to use well water for personal consumption.

Homeowners interested in having their water tested are provided with bottles for sample collection and simple instructions. However, in some cases, Nashoba Analytical will send staff to conduct the tests. Each test is specific to the property. After E. Coli, some of the most common tests are for lead, arsenic, nitrates and mercury. Bacteria tests are cultured in the lab and incubated, while metals and wet chemicals are analyzed with various instruments in the lab.

Radon is becoming a more common test, though standards for air and water differ for this gas. While airborne radon has a formal limit, water testing is still just a guideline, or strong suggestion. Test prices range from $20 to $150 and are a crucial investment in public health, especially in an area where wells are so common. For example, Harvard’s water supply is 90 percent well water and Carlisle’s is 100 percent. A minimum of testing once per year for coliform and a comprehensive test every three to four years, especially if water appears to change, is recommended.

It takes a special couple to make a business work while not bringing it home at the end of the day. Both Knowltons agree that the best part of their venture is owning their own business. The downside is the lack of vacation time, but they are on peak demand while the business is still growing. Dave noted that the hours a new business demands rival that of farming, but both feel that it has paid off.

Like most successful people, the Knowltons manage to keep up with their hobbies in the rare moments not dedicated to the business. Dave is an active apprentice in the American Bladesmithing Society who also plays the trumpet and enjoys working on classic cars. Rachel loves to bake and is currently learning to play the piano. But water quality is never far from their minds.

Though municipalities make up the bulk of Nashoba Analytical’s client base, they also have a large volume of private property owners. The good news is, less than 5 percent of tests turn out to be unpotable. In fact, bottled water safety is statistically the same as 99 percent of tap water in Massachusetts.

“There’s a lot of safe water out there,” Knowlton said.