Private Wells – Windham

Most of Vermont is underlain with rock and the early settlers must have relied on springs, streams and catching rain water. Water is heavy and building your home as close to potable water as possible is obvious.

The first documented spring-pole well in America was drilled in 1806 by David and Joseph Ruffner in West Virginia. It reached 58 feet in depth, containing 40 feet of bedrock. The project lasted two years.

The spring-pole was a contraption where a pulley attached to a pole anchored at one end and the other end raised so that the pulley was suspended over the developing well. A weight attached to a rope running through the pulley is lifted and then dropped into the developing well. Each drop cracked the stone and those particles were probably collected using another pipe with a flap valve lowered into the water filled hole and withdrawn to remove the particles.

This laborious process has given way to more modern techniques and we are now able to drill wells and build houses just about anywhere. But it is not cheap – current estimates for drilling a 400ft well and installing a pump can be upwards of $25,000.

In a July 2019 paper titled “Deeper well drilling an unsustainable stopgap to groundwater depletion1” the authors say “We expected to find that wells were being drilled deeper in California’s Central Valley, and our expectations were confirmed,” Jasechko said in an email. “I was surprised how widespread deeper well construction is in other parts of the USA that are not studied as often, such as Iowa, Missouri and Vermont.” I wanted to confirm their assertion that Vermont wells are deeper as time goes by. In 1966 Vermont began requiring well drillers to file a certificate of completion with the state and that would appear to be a good data source. As usual, one needs to take a look at the data before placing too much reliance on it and to do that I downloaded it and loaded it into my GIS application.

Whoops! I could see problems right away; many wells are not in the correct location, data is missing, and I found some apparent data entry errors. I did contact the state to notify them of this and the person writing back had taken some time to investigate it on his own and he replied,

“Thanks for the note. One of the challenges of coordinating the publishing of statewide GIS data is clarifying who is the steward of a particular dataset, as the Geodata portal contains items overseen by multiple partner agencies. In the case of well data, ANR is the publisher and steward, and the folks in the drinking water division who would happy to know this info are:

Scott Stewart Scott.stewart@vermont.gov or Grahame Bradley Grahame.bradley@vermont.gov

In addition to that, another ANR colleague let me know that there is a relatively new online form for reporting missing/incorrect well data. (If curious, well mapping is described in this post https://medium.com/vcgi/mapping-vermonts-water-use-f0d4beb23679 ). There is also a link to that update form accessible via the ANR Atlas, where you can turn on the “Private Wells” layer, click on the point location of the well in question, and in the pop-up box select to update the well location/report incorrect well location.” So they are aware of the problems and are trying to improve the data.

I did update the location for my well and I encourage Vermonters to check their data and to update if if necessary. It is unlikely that Windham will have a situation like the recent PFOA problem, but knowing where your well is should there be a problem with the pump, nearby construction and things like that is a good idea. It is also much easier to be pretty precise using today’s gps enabled cell phones.

Knowing the data I had was inaccurate I wanted to glean something from it and used the town, date completed, and well depth. I loaded the gis attribute table into R Studio and created a scatter plot with a trend line (Town of Windham only) and it does appear the the wells in Windham are getting deeper as time goes by. At the outset in 1966 the average depth was around 150ft and in 2018 the average is 300 ft. However, I think the reasons for that are different from those in California’s Central Valley. In California they probably are going deeper for more irrigation water, but here in Windham I can think several reasons for this: Windham has high mountains to the east and west and the valley is where most houses are. Improving equipment makes it possible to drill deeper and in just about any location and many people want a view of beautiful Vermont from their front deck so they choose a house site at higher elevations. Below is a scatter plot showing the 290 or so Windham wells in the database. The y axis is the well depth and the x axis is the date completed for each well. The blue line shows the upward trend of well depth. The grey area alongside the trend line is the .95 confidence level.

1https://www.nature.com/articles/s41893-019-0325-z