Thompson Lake Dam

PUBLIC NOTICE:

NOTICE OF INTENT TO FILE

Please take notice that Town of Oxford, 85 Pleasant St. Oxford, ME  04270 207-539-4431 is intending to file a Natural Resources Protection Act permit application with the Maine Department of Environmental Protection pursuant to the provisions of 38 M.R.S. §§ 480-A thru 480-BB on or about June 20, 2019.

The application is for Thompson Lake Dam Rehabilitation at 293 King St. Oxford, ME.

A request for a public hearing or a request that the Board of Environmental Protection assume jurisdiction over this application must be received by the Department in writing, no later than 20 days after the application is found by the Department to be complete and is accepted for processing. A public hearing may or may not be held at the discretion of the Commissioner or Board of Environmental Protection. Public comment on the application will be accepted throughout the processing of the application.

The application will be filed for public inspection at the Department of Environmental Protection’s office in

Augusta during normal working hours. A copy of the application may also be seen at the municipal offices in Oxford, Maine.

Written public comments may be sent to the regional office in Portland, Augusta, or Bangor where the application is filed for public inspection:

MDEP, Central Maine Regional Office, 17 State House Station, Augusta, Maine 04333
MDEP, Southern Maine Regional Office, 312 Canco Road, Portland, Maine 04103
MDEP, Eastern Maine Regional Office, 106 Hogan Road, Bangor, Maine 04401

A Public Informational Meeting will be held on June 20th, 2019 at 6:30 PM at the Oxford Town Office, 85 Pleasant Street to discuss the project.

Water Level Changes – Thompson Lake Dam History

From the Original Document submitted by the TLEA dated

August 30th, 2012

The Thompson Lake Environmental Association examined the issue of lake water level draw down in the fall and the target level for the lake for winter. After extensive review of the historic records and conversations with biologists and managers of dams in the area, targets were established.

Dam control is a means to significantly reduce the threat of soil erosion dumping phosphates into the water.  Maintaining shoreline integrity helps minimize undermining large trees that would fall into the lake as well. According to lake biologists, the largest soil erosion comes from erratic water levels, especially those above or below what is called the “cobble zone” ( the zone is where the rock and pebble composition is at the highest).

Between 1966 and 1986 the average winter water level was 37.1 inches below the top of the dam.  In the following  years winter water levels were left significantly higher, resulting in spring flooding and erosion. In order to keep the water levels in the cobble zone it was decided to target the winter level at 32 inches.

The water draw down will start around October 1st and finish by October 20th to the winter level of 32 inches.

The schedule has multiple considerations:

  • To preserve boat navigation in the shallow areas until Columbus Day Weekend.
  • To protect the lake trout spawn which starts in mid October and finishes in early November.
  • Working with the capacity of rapid water draw downs by using just the spillways and not the center gate

Several Important Facts:

  • In heavy rainfall conditions, 1 inch of rain results in roughly 2 inches of lake level rise.
  • The maximum water release of 2.5 inches a day is very feasible utilizing the spillways.
  • With all of the planks in place the spillway lake level is approximately 16 inches which is the maximum acceptable level. (Prior to 2012 and the TLEA research, the lake level was approximately 14 inches with all planks in place)
  • When a storm is forecasted to drop 2 or more inches of rain while the lake is at 16 inches or closer to the top of the dam, a preventative water release should be done the day prior.

Thompson Lake Levels and flow

The table below shows the level of both Thompson Lake and the flow of the stream.

Reading the Table:

The goal for the summer lake level is 16.  Due to evaporation and drought situations the level often falls below the desired level. Rain fall amounts also affect the lake level bringing it up faster then it drains out.

Above is an example of a gauge in feet

In the Chart Below, when reading the level in inches, we are reading from 0 being at the top of the gauge and measuring down to the water level. The higher the measure in inches the lower the Lake water level is.

When reading the  TLOS Gauge in feet the lower the number, the lower the stream water level.See chart below for both gauge readings.

If Levels are  below 4.12, CFS is unavailable.

2019 Thompson Lake Levels

2018 Thompson Lake Levels

December 2017 levels

November 2017 levels

Thompsonlakelevels2

  • To protect the lake trout spawn which starts in mid October and finishes in early November.
  • Working with the capacity of rapid water draw downs by using just the spillways and not the center gate

Several Important Facts:

  • In heavy rainfall conditions, 1 inch of rain results in roughly 2 inches of lake level rise.
  • The maximum water release of 2.5 inches a day is very feasible utilizing the spillways.
  • With all of the planks in place the spillway lake level is approximately 16 inches which is the maximum acceptable level. (Prior to 2012 and the TLEA research, the lake level was approximately 14 inches with all planks in place)
  • When a storm is forecasted to drop 2 or more inches of rain while the lake is at 16 inches or closer to the top of the dam, a preventative water release should be done the day prior.
Town Office Hours
Monday, Tuesday, Wednesday, and Friday
8:00 AM to 4:00 PM

Thursday
10:00 AM to 7:00 PM

Contact Information
P.O. Box 153
Oxford, Maine 04270
Phone: 207-539-4431
Fax: 207-539-4228
Our office will be closed on the following days
Jan 1 New Year's Day  Tuesday
Jan 21 Martin Luther King Day Monday
Feb 18 Presidents' Day Monday
Apr 15 Patriots Day Monday
May 27 Memorial Day Monday
Jul 4 Independence Day Thursday
Sep 2 Labor Day Monday
Oct 14 Columbus Day Monday
Nov 11 Veterans' Day  Monday
Nov 28 Thanksgiving Thursday
Nov 29 Thanksgiving Friday
Dec 24 + 25 Christmas Tuesday Wednesday

All Days that Elections are held, June and November.

Topics of Interest

Tax Information

Employment Opportunities

Town Ordinances

Request For Proposal

Board of Selectmen Agendas and Minutes

CONTACT US

P.O. Box 153
Oxford, Maine 04270

Fax: 207-539-4228

Phone: 207-539-4431