EVERSOURCE Energy is making some changes to the 115 kV transmission system in northwestern Connecticut.

The biggest change will be the addition of a new 115 kV transmission line running between the FROST BRIDGE and CAMPVILLE substations. See the above illustration for details.

FROST BRIDGE is a large transmission substation that steps 345 kV down to 115 kV. CAMPVILLE steps 115 kV down to 27.6 kV, and features a switching area for two 115 kV circuits that head up to Torrington, CT. THOMASTON is a mid-sized distribution substation that steps 115 kV down to 13.2 kV.


Left to right: FROST BRIDGE to CAMPVILLE 115 kV, CAMPVILLE to THOMASTON 115 kV


The current CAMPVILLE to FROST BRIDGE 115 kV transmission line (pictured to the left in the photograph above) was built in the 1930s by the Connecticut Power Company. It uses bundled copper wire (two conductors per phase) supported on wooden H-frames. EVERSOURCE replaced most of the H-frames in 2015 and 2016.

A new circuit is going to be added along this route, likely constructed on non-galvanized steel monopoles using brown LAPP disks.

The CAMPVILLE to THOMASTON line (pictured to the right in the photograph above) was constructed in 1969/1970, and uses laminated wooden poles and davit arms, with 'sky yuk' disks. It is possible that this line will be rebuilt where it shares the right-of-way with CAMPVILLE to FROST BRIDGE.



Left to right: FROST BRIDGE to BETHEL 345 kV, FROST BRIDGE to CAMPVILLE 115 kV, FROST BRIDGE to BULLS BRIDGE 115 kV.


The FROST BRIDGE to BULLS BRIDGE 115 kV line was constructed on steel monopoles and consists of one circuit. No major work is known to be planned for this line.

The FROST BRIDGE to BETHEL 345 kV line was originally constructed in the 1960s on wooden H-frames. EVERSOURCE replaced all the wooden H-frames with steel units in 2015 and 2016. No further work is known to be planned for this line.


UPDATE: APRIL 23, 2016

Below is a photo of a new H-frame on the FROST BRIDGE to CAMPVILLE 115 kV line:



These H-frames use sky yuk disks, and were constructed in 2016.

EVERSOURCE is also doing some work to replace poles and add a new circuit where the company's ROW (and two extant 115 kV lines) cross the Naugatuck River. The photos below feature the Naugatuck River crossing, taken from the west (first photo) and east (second photo).

The Naugatuck River runs alongside Connecticut Route 8, featured in the map at the top of this article.



Top to bottom: Naugatuck River crossing viewed from west, Naugatuck River crossing viewed from east.

The photos below feature closer views of the construction going on at the Naugatuck River crossing.


New monopoles being erected on the western side of the Naugatuck River crossing.



New monopoles being erected on the eastern side of the Naugatuck River crossing.