Monday, September 23, 2019

Painting River Depth Markers

The Assabet River, as it flows through Maynard, has an average volume of 200 cubic feet per second (cfs). Month-by-month, March and April average 400 cfs, while July, August and September average under 100 cfs. Drought can drop flow to 20 cfs. There is an internet-accessible gauge of river volume and depth, found by searching on USGS Assabet. The default is showing the last seven days of data, but a larger number of days can be selected.

At 100 cfs, depth is 2.0 feet, 200 cfs = 2.5 feet, 300 cfs = 3.0 feet, 400 cfs = 3.5 feet,
1,000 cfs = 5.0 feet, 1,700 cfs = 6.0 feet, and 2,400 cfs = 7.0 feet. The last significant flood was spring 2010, 2,500 cfs = 7.1 feet.
Wall under John's Cleaners, bordering the Assabet River in Maynard, MA, as
seen from the middle of the Main Street bridge. Click on photos to enlarge
While checking USGS Assabet is rewarding to data advocates, the idea of providing a publicly seen measure of water depth was a challenge. One location seemed ideal - the wall under John's Cleaners, bordering the Assabet River, next to the Main Street bridge.
Walking in the Assabet River from Tobin Park (north of the Rail Trail bridge)
 to the Main Street site, where a ladder had been lowered by rope.
As this was to be a very public project, seeking permissions seemed like a good idea. Queries to Town of Maynard management, including Department of Public Works and Conservation Commission, resulted in conditional approval. Facts learned in the process were that the Commonwealth of Massachusetts 'owns' the water in the river, the Town owns the land under the river, and private property owners own land down to mean high water. What this meant was that John's Cleaners owns the wall, so permission was sought there, also. Finally, the project was proposed to the Board of Selectmen - and approved. A waiver was signed to absolve the Town of any liability in case of injury.
Using duct tape to attach a stencil to the wall. Two stencils were created, each five feet long
one taped above the other. The material was FedEx boxes. Making the stencils took four hours.
Stencils were created from FedEx corrugated boxes, incorporating five inch tall number stencils. Creating the stencils took about four hours. The duct tape and stencils were lowered by rope from the bridge. Discarded after the one-time use.
The paint use was Benjamin Marine D.M.T. Acrylic "Safety White,"
suitable for use in places that will be wet or under water.
From arriving at the site to completion of the painting took about one hour, including the walk in from and out to Tobin Park, which was over water-plant slicked rocks under one to two feet of water. The ladder was needed to tape and then paint the top of the upper stencil.
About to paint the top markers and numbers. Nine feet was chosen because since record
keeping began in 1942, no flood has exceeded nine feet, and only five have exceeded seven feet. 
Water depth records collected by the U.S. Geological Survey (USGS Assabet) are for the gauge near the 7-11 store, and thus water depth at the bridge is not an exact match. The USGS defines the Assabet River as being in flood stage when depth exceed five feet. This happens at least once almost every year.
Wall painted, stencils removed. Except in time of extreme drought
the water is never low enough to paint a marker for one foot.
Historically, for floods for which water depth was measured, Hurricane Diane raised the river to 8.94 feet (at the gauge) in 1955. Floods in 1968 and 1979 reached 8.1 feet. Floods in 1987 and 2010 reached 7.1 feet. Volume at that 2010 flood was recorded as 2,500 cubic feet per second.
The wall, with water depth markers.
River depth is of interest to kayakers. Currently the river between the Ben Smith Dam and the east side of Maynard is blocked by many fallen trees, but if ever cleared (by Town of Maynard, or a significant flood), it is possible to kayak through town - under the bridges - when water depth is more than 2.5 feet and less than 4.0 feet. Too low, get stuck on bottom. Too high, get stuck under bridges.

Wednesday, September 18, 2019

Assabet Cleanup 2019

The 33th Annual River Cleanup took place on September 14, 2019. Teams volunteers were assigned locations along the Assabet, Sudbury and Concord rivers. In Maynard alone, decades of annual river clean-ups organized by the Organization for the Assabet, Sudbury and Concord Rivers (OARS) have removed tons upon tons of trash. This year, the focus was on trash, plus invasive and riverview-obstructing plants at Tobin Park, just west of the Rail Trail bridge.

One visible gain from cleaning up the Assabet River is that progressively, over the years, less new trash ends up in the river. The “broken window theory,” first in print in 1982, holds that vandalism is contagious, i.e., unrepaired vandalism triggers more vandalism, and perhaps more controversially, triggers an increase in more serious crimes. In theory, zero tolerance for small crimes reduces the rate of large crimes. Whether true or not for criminal behavior, littering is clearly contagious – the more litter remains visible, the more likely people will litter more.

Tobin Park, Maynard, 2019 Assabet River cleanup. Click photos to enlarge. 
This appeared to be a watershed year (pun intended), as Maynard had more volunteers than trash to be removed from the river. Past years had yielded as many as 100 car and truck tires, plus bicycles, shopping carts, and tons of iron pipe, scrap metal, broken pottery, old carpets and miscellaneous junk. This year, only two tires, one Styrofoam cooler and an estimated total of less than 200 pounds of glass, metal and plastic. Clearly, less and less is being thrown into the river each year. Hurrah! Similar results were reported for other towns.    

Glass bottle, 1953: CALDWELL'S RUM
Past years have also included intact glass bottles with a bit of history. From 2010, the find was a bottle inscribed HALF PINT LIQUID, HANS ERIKSEN, MAYNARD, MASS. The name’s spelling dates the bottle, because it was after World War II that the family, which was then also in the milk delivery business in addition to ice cream, changed their name from Eriksen to Erikson. From 2013 the find was an amber glass pint bottle embossed with the words CALDWELL'S RUM and the image of a three-masted sailing ship alongside a dock. The company had been started by Alexander Caldwell in 1790. Markings on the bottom signified that the bottle had been made for Caldwell's Rum in 1953 by the Anchor Hocking Glass Company. The yield from 2016 was a plain glass bottle with NEW ENGLAND VINEGAR WORKS embossed on the bottom. Turns out NEVW began its life in 1865 in Somerville as the Standard Vinegar Company. The name was changed to New England Vinegar Works in 1907. Another old find was a small bottle embossed with TURNER CENTRE SYSTEM, representing a dairy bottling and home delivery company active 100 years ago. 

As to the means by which thousands upon thousands of glass bottles ended up in the stretch of the Assabet as it wended it way through Maynard, think bridges and backyards, and the opinion that anything disposed into the river went "away." This is not a new problem. From the 1913 Annual Report of the State Board of Health "The Assabet River has at various times been seriously polluted in different parts of its course, the most serious condition in recent years below Maynard where the river receives sewage and manufacturing waste from a very large woolen mill and a considerable quantity of sewage also from the town... the river continues to be objectionable in appearance and odor, especially below Maynard."

Click on image to enlarge. Cumulative score for lower
Assabet River is a B. Weaknesses in yellow. Bacteria is a
planned future score, hence grey.
Going forward, OARS may consider its means of using volunteers for its fall event. Recently, a river health Report Card was created to assess the health of the three rivers, with each river divided into upper river and lower river sections. Based on twenty criteria listed at, the Assabet from headwaters to Elizabeth Brook, in Stow, was graded C+ and the lower Assabet – from Elizabeth Brook to the convergence with the Sudbury River – was graded B. Weaknesses include dissolved nitrates in the water (from fertilizer runoff and effluent from wastewater treatment plants), floating biomass (algae and duckweed on the surface) and aquatic connectivity (because the Ben Smith and Powdermill dams prevent wildlife movement up and down river). In the future the OARS Cleanup may expand to sending crews out to improve river-bordering trails, passability and riverviews. There are no current plans to remove any of the dams on the upper or lower Assabet.

Photos for this year's effort will posted at the OARS website.

Wednesday, September 11, 2019

Death by Exercise

Sudden cardiac death – as in the college-age basketball player or the hyper-fit triathlon participant – tends to make the news. As it should. Newsworthy death while exercising provides every non-exerciser with rationale for not exercising. “See” they say, “this person was an avid runner [cyclist, swimmer] and dropped dead at 40.” The contrarian point being that the endurance sports that are supposed to protect against heart disease sometimes appear to do just the opposite.

There is a wisp of truth to this observation. Estimates are that just under one person per 100,000 participating in a marathon, or 1.5/100,000 participating in a triathlon will die during or immediately after the event. Figure a collective three million participants in these types of races and that comes to maybe 30 to 40 deaths per year. There are fuzzier estimates of perhaps one sudden death per every million exercise events for other forms of vigorous exercise. So, the true answer is yes, exercise can kill the physically fit, but no, not a risk factor worth avoiding exercise entirely.

Internet image portraying a man having a heart attack while exercising.
There is more truth in the observation that exertion by the physically unfit can result in fatal cardiovascular events. The classic case is the middle-aged office worker who drops dead shoveling snow while attempting to clear the driveway and get to work. Contributing factors include the fact that blood pressure peaks in the morning a few hours after waking up, and the fact that exertion in cold weather constricts arteries, further adding to heart stress. Snow removal related heart attacks frequently occur in women and men with no known pre-existing heart disease.

Exercise can also result in accidental death. In the U.S., walking, running, bicycling, swimming, boating and winter sports add up to about 10,000 deaths per year. Subtract half who are either children or are adults under the influence of alcohol (as in walking or riding a bike home from a bar, at night), and it’s still a big number. But the total pales compared to the 2,800,000 total deaths per year, of which many are premature cardiovascular deaths brought on by a lifetime of inactivity.

The good news is that benefits from even modest amounts of exercise are becoming clearer. The American Heart Association recommends adults get at least 150 minutes per week of moderate-intensity aerobic activity or 75 minutes per week of vigorous aerobic activity, but notes that even a few minutes per day was better than nothing! Studies have reported the greatest improvement for modest exercise compared to no exercise at all, and diminishing but still cumulative returns for progressively more exercise. A recent article in the Journal of the American Medical Association reported that endurance fitness was a better predictor of good cardiovascular biomarkers (cholesterol, etc.) than strength.

The theory that aside from injuries, over-doing exercise may cause more harm than good has been disproven. A science journal article reviewed studies of longevity of elite athletes. Athletes from endurance sports had 3-6 year longer life spans than the general population. The authors cautioned that elite athletes may by genetically different from the population as a whole, with both their abilities and lifespan being consequences of their genes rather than one causing the other. A review article encompassing 48 published studies confirmed that people doing as much as 7-14 hours per week of moderate to vigorous exercise were had a 15 percent lower mortality risk than those doing only 1-2 hours per week, with no hint that the benefit fades toward the high end.  

There is a non-fatal problem with exercise – it is potentially addictive. As one well-known fitness expert author put it, “…people reduce their lives to fitness routines, training as many as 40 hours a week. That the effort may wreck marriages and compromise immune systems isn’t even relevant. To these people – demographically a diverse lot – exercise is addictive. The more the body gets, the more it wants. In return, the drug of exercise infuses the swimmer, cyclist and runner with two powerful illusions: that he/she is escaping the horrible, and progressing toward the divine.”