Connecticut laws/regulations;

OLR Research Report

September 21, 2011




By: Kevin E. McCarthy, Principal Analyst

You asked about the laws that govern tree trimming by electric companies and the companies' trimming programs.


The law generally requires the electric companies to get the consent of the adjoining property owner before trimming any tree that is on or hangs over a highway or public property, but provides mechanisms for trimming if the owner does not consent. The law also requires the electric companies to submit annual plans to the Department of Energy and Environmental Protection (DEEP, formerly the Department of Public Utility Control) for maintaining their systems, which include tree-trimming programs.

This report describes Connecticut Light and Power's (CL&P) plan and programs, which are available at

http://www.cl-p.com/templates/faq.aspx?id=4294986424&terms=TREE. The tree trimming programs are found in Appendix 3. United Illuminating has a similar plan and programs.

Under CL&P's programs, trees near distribution lines are normally trimmed every five years. Trees are trimmed to clear eight feet on sides of the line, 10 feet below the line, and 15 feet above it. Trees in areas subject to frequent outages are trimmed to greater clearance.


CGS 16-234 bars electric and telephone companies from cutting or trimming any tree on a highway or public ground or that hangs over such property without the adjoining property owner's consent. If the company cannot obtain the owner's consent, it can cut or trim the tree with the approval of the town tree warden or DEEP. The tree warden or DEEP can only consent after a hearing with notice to the property owner. The hearing must be held within a reasonable time after the application for cutting or trimming the trees.

CGS 13a-140 allows the Department of Transportation (DOT) to cut, remove, or prune any tree or vegetation within the limits of a state highway so far as this is reasonably needed for safe and convenient travel on the highway. No person or entity may cut, remove, or prune these trees or vegetation without first obtaining a DOT permit, but this does not limit the rights of utility companies to cut and trim trees and branches and otherwise protect their lines, cables, and other equipment from encroaching vegetation.

CGS 16-32g requires each electric company to submit to DEEP an annual plan for maintaining poles, wires, and other fixtures along public highways or streets that are used to transmit or distribute power. The plan must include a (1) summary of appropriate staffing levels needed for maintaining the fixtures and (2) program for trimming branches and limbs located near overhead electric wires that may damage them. DEEP must review each plan and may issue orders as necessary. DEEP may require each electric company to submit an updated plan containing information it prescribes. DEEP must adopt implementing regulations.

CL&P's 2011 plan notes that:

In most cases, [owner] denials are resolved and either a partial or a full trim is allowed. In general, tree trimming denials do not represent a major obstacle to CL&P achieving its tree-trimming goals because they represent a relatively small number of miles when compared to the total number of miles trimmed. In 2009, there were 397 tree trimming refusals. Through October 2010, there were 344 refusals.


According to CL&P, during the course of a year, trees are responsible for approximately 25% of all outages and more than 90% of storm-related outages. Company and contractor crews trim trees on a cycle that generally results in all trees being trimmed every five years. This work is performed year round. Licensed arborists employed by the company oversee contractor crews that work on trees. In the event of severe weather or widespread outages the number of contractors increases substantially.

According to CL&P, the company or contractor informs property owners and right-of-way abutters with homes or buildings located within 200 feet of the right-of-way, with maintained property to the edge of the right-of-way, or within the right-of-way area of the proposed work at least 48 hours before it starts. DOT must consent to the trimming of trees in the right of way of state highways. For other trees located on public property, the town tree warden must give consent. Before any tree work can be performed on private property, the company or its contractors must obtain consent from the tree owner. Consent may be requested in person if the owner is at home; if not door hanger requests are left for the owner. In practice, if the owner does not respond within the amount of time specified on the door hanger, the crew will begin its work.

In trimming individual trees, the crew must consider the tree's species, condition, growth rate, and location. In most case, trees are trimmed to clear eight feet on the sides of the line, 10 feet below the line, and 15 feet above it. In areas that have experienced frequent outages, trees are trimmed to 20 feet above the line. If the existing clearance between the line and the trunk or a branch that is more than six inches in diameter is less than these distances, the crew is directed to leave the trunk or branch but remove all other branches in the clearance zone. If trimming the clearance area would remove more than one-third of the tree's leaves, the tree will normally be removed instead. But the owner's consent is required to do this to large trees (those with a diameter of 16 inches at chest height).

Branches are trimmed using a tree-care industry technique known as target pruning. Each branch is pruned back to where it meets the branch collar so that the pruning cut will callous over and prevent decay of the pruning wound.

Trees that are decayed, insect-infested, damaged, or structurally weak may be removed. Small trees and saplings that are capable of growing into the conductors are normally removed before they grow tall enough to interfere with the lines.

In the case of lines located away from rights-of-way, the company either owns the land outright or holds an easement on the land under the line. Ownership or an easement gives the company the right to remove vegetation that is hazardous to its facilities or restricts access along the right-of-way. To keep the lines, access roads, and facilities clear of interfering vegetation, all tree species capable of growing tall enough to contact the overhead conductors and shrub species that may restrict access to the facilities are removed manually, mechanically, or controlled through the use of herbicides.