Wednesday, May 19, 2021

Assabet River: Floods and Droughts

On May 24, at 7:00 p.m., the Maynard Public Library will present a Zoomed talk titled: “Assabet River Floods and Droughts.” Register (free) at This is the fourth in a monthly series of history lectures produced by the Sesquicentennial Steering Committee as part of Maynard’s celebration of the 150th anniversary of its creation on April 19, 1871. The June talk will be “Digital Equipment Corporation.” A new history book “MAYNARD MASSACHUSETTS: A Brief History” is for sale for $21.99 at 6 Bridges Gallery, 77 Main Street, WED-SAT, 12-5.

The Assabet River is a short (34 miles) river, meaning that its entire watershed of 177 square miles can be impacted by a single storm system. As a result, a flood situation can develop quickly. Data shows that timing from beginning of a storm to peak flow through Maynard is about 48 hours. The Sudbury River is equally short (33 miles), and both have their headwaters in Westboro, but much of the lower Sudbury crosses nearly flat terrain, with a wide flood plain. Thus, at the point where they join to become the Concord River, flood conditions on the Assabet reach the juncture faster, in fact so fast that there are instances when water discharging from the Assabet causes the Sudbury River to flow backwards.        

Main Street bridge, March 2010
The Assabet River is officially declared at ‘flood’ state when the U.S. Geological Survey gauge situated upstream from the Waltham Street bridge reports a depth of five feet, which happens when volume reaches 1,000 cubic feet per second (cfs). Historical records show that about every 10 to 15 years or so either a fall hurricane or spring rains flooded the Assabet. Often the cause was two storms – one to saturate the soil and the second to flood the already partially raised river. At five feet, the river is still entirely within its banks, just moving fast. Six feet means a volume of 1,700 cfs, seven feet 2,400 cfs, eight feet 3,400 cfs and nine feet 4,400 cfs. Eight feet puts water into the mill buildings next to the river. Nine feet, reached in 1927 and 1955, puts water on Main Street, floods the Elks Lodge parking lot, and in 1927, severely damaged the Waltham Street bridge. The last major flood, March 2010, saw 15 inches of rain from several storms, and a flood level of 7.1 feet. The last flood before that was 1987, also a bit over seven feet. Neither caused any significant property damage in Maynard.

Main Street bridge, August 2010

The 1968 flood (8.15 feet) put water over the retaining wall between the river and the mill complex, necessitating frantic sandbagging and pumping to minimize damage at Digital Electronic Company. One-time DEC employee Jack MacKeen recalled, “I have a clear mental picture of Ken Olsen [President of Digital Electronic Corporation] in his suit and rubber boots, helping place sandbags between the buildings.” Afterwards, DEC had the river retaining wall on its side of the river built higher. The wall kept the river out of the mill complex during the equally high flood of January 1979.

Contributing to the fact that the Assabet River has not suffered a catastrophic flood since 1955 are three major flood control dams. The George H. Nichols Dam, Westborough, completed in 1968, created a reservoir of a more than half a square mile which serves as a recreational boating and fishing site. It holds back high water and also serves as a water supply for the Assabet River in times of drought. Tyler Dam, Marlborough, does not obstruct any flow during normal river conditions, but backs water into an otherwise swampy impoundment area during high water. The third major holdback is the Delaney Complex, on Elizabeth Brook headwaters, completed in 1971. There are also more than a dozen minor flood control structures on tributaries. Collectively, these and the historic dams on the Assabet have a holdback capacity of more than four billion gallons of water, thus preventing millions of dollars of property damage. 

Precipitation is inches per month; Assabet
River volume is cubic feet per second, by month
Low water on the Assabet River is not due to less rain during the summer months, as the watershed averages close to four inches of precipitation every month of the year. There are several causes: 1) more of summer rain evaporates into warm summer air, 2) plants take up water and release that into the air via evapotranspiration; 3) surface soil, not frozen, absorbs water and transfers water to the aquifer. The result is that July, August and September average a flow of about 50 cfs. However, almost every summer there are weeks without rain when the flow is reduced to 10-20 cfs. Whenever flow falls below 39 cfs the owners of the mill complex are prohibited from diverting water from the river into the mill pond.

Massachusetts established a Drought Management Task Force in 2001, charged with monitoring drought conditions and advising water restriction policy as status goes from Normal through Advisory, Watch, Warning and Emergency. For our region, the last time Warning was reached was the 2016-17 drought. Locally, Level 3 water-use restrictions were enacted.

There was an exceptionally severe, state-wide, multi-year drought in 1961-69. Assabet flow reached a record low of 2 cfs. Prior to the drought, dating back to 1889, Maynard sourced water from White Pond, which is located on the Stow/Hudson border, south of Lake Boon. Miles of pipe and a pumping station moved water from the pond to a tank constructed atop Summer Hill. Starting in 1963, Maynard began transitioning to sourcing its water from town-owned wells. The town switched to getting all of its water from wells in 1999, after federal water treatment standards for surface water sourcing were made more rigorous. Maynard is perennially considering reviving White Pond as a water supply. A 2019 report estimated the cost of building a water treatment plant and installing miles of new pipe at about $30 million dollars.

A note about summer river flow: upriver from Maynard are now three municipal wastewater treatment plants that discharge water into the river. (Maynard’s discharge is at the Maynard:Acton border.) During summer lows, roughly half of what flows through Maynard represents processed wastewater. Per current state requirements, that water is “...cleaner than the river it is put into.” Overall, the river is far, far cleaner than it was years ago, when mill waste and sewage discharge was poorly regulated. As Ann Zwinger wrote in a 1982 book – A Conscious Stillness – “...the reach above the Powder Mill Dam is closed by joint action of the Maynard and Acton boards of health...the river smell is nauseating, reeking like an unpumped-out campground outhouse times ten."

Click on photo to enlarge
Summer of 2019, Mark painted water depth markers on the wall below John’s Cleaners, visible from the Main Street Bridge. This required permission from the Conservation Commission, Department of Public Works, Town of Maynard Selectmen and the owner of the building. Also, the signing of a liability waiver, and notifying the police department on the day of the painting, that a person would be in the river, near the bridge.


Wednesday, May 12, 2021

Cicadas? - Not Here (eastern MA)

Shell left behind after the cicada emerges from
underground, splits the back and flies away.
For 17 years, cicadas of the infamous cicada swarms do very little, and none of it above ground. They suck sugar out of tree roots. Then, following this absurdly long subterranean life, they emerge, sprout wings, make a ton of noise, have sex, lay eggs and die.

“Brood X” is emerging from its 17-year underground sequester this year, but not here. Brood XIII will emerge in 2024, but not here. Brood XIV will emerge in 2025, but not here. According to a map created by the U.S. Department of Agriculture Forest Service, identifying 15 periodical cicada broods that affect (afflict?) the United States, none of them are present in the greater Boston area. However, if you intend to visit parts of New Jersey, Pennsylvania, Delaware, Maryland, Ohio, Indiana, Kentucky, North Carolina or Tennessee this May or June, you will be sharing the great outdoors with billions upon billions of their discarded nymph shells, the noisy cicadas, and then their carcasses once they all die. And by noisy, meaning four to six weeks of lawnmower-loud males, all making a high-pitched buzz in their attempts to attract females. Note how different this is from moths, wherein the females release pheromones into the air, and males detect those molecules with their antennae.    

Cicadas mating
World-wide, there are more than 3,000 species of cicadas. Locally, the annual cicada actually has a life cycle of 2-5 years underground as a nymph before emerging to become a dark-bodied, dark-eyed adult, during late July and August. Although these take several years to mature there is no synchronization, so numbers are similar every summer, and the term “annual cicadas” is commonly used. Only in the eastern United States are there also the “periodical cicadas” which synchronize to either every 17 or 13 years (duration different for different species within the genus Magicicada).  

The life cycle of periodic cicadas has two mysteries: Why? and How? Long life cycles may have developed as a response to predators, such as the cicada killer wasp or praying mantis. The thinking is that specialist predators with a shorter life cycle could not reliably prey upon the cicadas, hence their population crashes during the following years. Generalist predators, such as many types of birds, snakes, racoons and skunks would in theory be subject to saturation of predator capacity, meaning that the predators at normal population density would eat all they could, yet not hinder breeding success. Skipping a small number of years between broods would not improve survival, as long-lived predators can increase in population right after the boom year, with those litters present in the immediately following years.

“How” is a mystery. First year, nymphs are not far below the surface, but after a few years of growth they are feeding from roots more than two feet below the surface, meaning that they are not getting any change of daylight duration or change of temperature signals. One speculation is that seasonal changes in the composition of root fluids are detected, but that still does not answer how the insects count to 17 (or 13). Another possibility is that the nymphs have an intrinsic molecular timing mechanism, such as ever-shortening DNA telomere length. Helping to keep the broods synchronized is the fact that those that emerge a year too soon or a year too late – having lost the count – are subject to severe predation, thus prevented from creating a new periodic population. Synchronizing the actual emergence appears to be linked to soil temperature, as global warming has shifted the timing a week or so earlier.

U.S. Forest Service Brood map. Brood X in yellsw
One way to think about the brood is as an acute increase in a protein- and fat-rich food appearing in a short period of time. Captured alive or scavenged after dead, these cicadas are delivering roughly 300 pounds (dried weight) per acre. Because it’s more than one million bugs per acre! Research shows that many bird species have better chick survival in brood years, followed by a population crash after.

Researchers recently solved one puzzle, which is how the cicada nymphs survive on nutritionally poor tree root fluid. Turns out, like termites, cicadas have symbiotic bacteria (in some species, fungi) that reside in their intestines, synthesizing the amino acids and vitamins their hosts need to survive. When the female creates eggs, the species in her gut microbiome are incorporated into the eggs.    

A color map showing all of the broods is available from the U.S. Forest Service

Although there are dozens of cicada recipes, Mark says he is not going to start to eat bugs.

NOT IN THE NEWSPAPER COLUMN: There are actually three species of 17-year cicadas, with different sounds. Males cluster in a 'chorus of cicadas' so that collectively their sound is louder. Females fly toward the sound. There is some evidence, that females select larger males. Females mate once. Males can mate more than once. 

Wednesday, May 5, 2021

400 Hundredth Column

"Prefers to be outdoors" Winter bicycling at 
below zero temperatures. (click to enlarge)
My first column was submitted November 2, 2009, published in the Beacon-Villager on November 12, 2009. As of May 2021, the count is 400 columns. That’s not including some 40 somewhat revised repeats. The running total is roughly 300,000 words and 350 photographs. The first four columns, all published in 2009, were titled "Stone Walls, Winter Bicycling, A River Runs Through it" and "Robins in Winter." Those were what had been submitted as examples for a column proposed to the editor of the paper, at that time Brian Nanos, to wit, a column to be named "Life Outdoors," with a scope that included Maynard and Stow history, observations on nature, and descriptions of outdoor recreational opportunities. The default byline at the end of each column was "Mark has an indoor job, but prefers to be outdoors." Brian's reply to the proposal was "Yes, but we can't pay you." 

More than eleven years and five editors since this began, the column continues. The editors have been Brian Nanos, Bruce Coulter, Caitlyn Kelleher, Joyce Crane, and – since August 2013 – Holly Camero. All of them have given me free rein to follow my curiosity, as long as most of the time the column topic was relevant to Maynard and/or Stow, and at length between 700 and 800 words, preferably submitted with a photo either of my own or from the collection of the Maynard Historical Society. At times, length has crept up to 1,000 words. The splits by category have been roughly 60 percent history, 20 percent nature, 15 percent recreational (bicycling, kayaking, hiking trails, etc.) and 5 percent health-related topics. The last stem from my science education and pre-retirement career in various health industry jobs. 

Productivity has been between 30 and 40 new columns per year, plus starting with 2014, five repeats per year of previously published columns, lightly reworked. The idea fountain has not yet run dry. There is always an ideas list of 10-15 potential columns, some as-name-only, some researched, and some partially written. Very often, ideas were generated by delving into the archives of the Maynard Historical Society, accessed either online or physically at the MHS collection, by randomly opening boxes of documents and photographs. Reader suggestions are always welcome.

Selling books at Farmers' Market
Many of the columns have had a post-publication life at and in three books: "MAYNARD: History and Life Outdoors (2011), Hidden History of Maynard (2014)," and "MAYNARD MASSACHUSETTS: A Brief History (2020)." The last is for sale at 6 Bridges Gallery, and at events scheduled throughout 2021 to celebrate Maynard’s 150th anniversary of its creation on April 19, 1871. For 2021, a selection of columns in the most recent book are the subjects of a monthly lecture series sponsored by the Town of Maynard Sesquicentennial Steering Committee and hosted by the Maynard Public Library. These can be attended as Zoomed talks or viewed later at the library website.  

Looking forward, there is no expectation of running out of ideas. A town does not have to be famous, nor date to the colonial era, to have had an interesting history. Or to keep creating history, especially if one’s definition of history is everything that has occurred up to this morning’s cup of coffee.

Sometimes history comes alive in a wonderful way. Soon after the movie “The Finest Hours” was released in 2016, an acquaintance mentioned that a Maynard resident had been involved. To wit, Edward A. Mason, Jr., Apprentice Seaman, age 23 at the time, was awarded the Silver Life-Saving Medal for his part in a 1952 Coast Guard rescue effort off the Massachusetts coast. When I went to see the movie at the Fine Arts Theatre, I mentioned the connection to staff behind the counter. The reply: “We know. Mason and his daughter were here this afternoon to see the movie.” I got a column out of it, and the Beacon-Villager interviewed Mason.

Lamson carving set
More recently, a column about an antler-handled, carving knife and fork set that had come into our family’s possession in 1961 delved into history about Silas Lamson, the 1834 co-founder of the company, then named Lamson & Goodnow. And then I got a note from a neighbor that she is a great-great-great-great-granddaughter of Silas Lamson.

Researching and writing for the Beacon-Villager has had collateral consequences. Information has been contributed to Wikipedia articles about Maynard, Massachusetts, the Assabet River and many other related topics. In May 2018, I was able to host a visit by seven descendants of Amory and Mary Maynard, great-great-grandchildren and great-great-great-grandchildren, and provide them with a tour of the town, including visits to the homes where Amory and Mary had lived, and inside the family crypt. Some of them were able to return, COVID vaccinated, to attend the April 19, 2021 celebration of the town’s founding, 150 years ago.

Mark had an indoor job (now retired), but prefers to be outdoors.