Summary--Required protection for trees during construction

The new tree protections--background

  Residents next to the Greenway have always been most concerned about the loss of trees from the project.  About 63--some quite large--are slated to be cut.  The project was designed to minimize cutting of trees--which means that many large trees not marked for cutting are just a few feet outside the cramped construction zone--just outside the orange fence.

During several meetings, Design Engineer Lisa Coleman assured residents that diligent efforts would be made to protect these "endangered" trees just outside the work area, although she cautioned there were no guarantees all would survive.

Alder Marsha Rummel took the lead in improving protections for trees:

"After the loss of street trees on Spaight Street [two summers ago] due to contractor negligence, I asked City Engineering and Parks staff to improve our practices to protect street trees during... public works projects." The same contractor is now working on our greenway.

"The new specs will inform contractors of our tree preservation practices during preconstruction meetings and require a sign-off to acknowledge that they understand our policies. Penalties will include a fine based on the diameter of the tree damaged due to negligence and the costs of removal, stumping, planting replacement trees, or pruning damaged limbs."

"Standards will be established for how close to a tree a contractor can grade or excavate, when to seek permission of the City Forester to cut roots, and a prohibition on parking equipment within 5’ of any tree to prevent soil compaction."

"Another improvement will be an enhanced letter to property owners that outlines the level of risk on a per tree basis."  Source

Summary of new tree protections

These apply to the "endangered" trees just outside the orange fence, and along where the lateral sewage pipes will be laid.
"It is recognized that grading operations, trenching and root cutting of these trees will need to occur within 5 feet of these trees in order to complete the work, but care must be taken in these areas." Grading, excavation, and trenching near these trees shall be done under the supervision of" an official "forestry representative."

In addition to the endangered trees just outside the fence, there are a few trees to be saved within the orange fence--these are at the east end of the greenway.

The four most common causes of damage to trees detailed below, along with required safeguards...

Root cutting
  • "Roots shall be cut cleanly by using a saw, ax, lopping shears, chain saw, stump grinder, or other means which will produce a clean cut. The use of a backhoe to cut roots is NOT acceptable.
  • All roots over one-half (1/2) inch in diameter that are damaged shall be cleanly cut immediately in back of the damaged section on the same day of the excavation.
  • The Contractor shall not rip or pull roots out towards the trunk while excavating with a backhoe. If in the opinion of the Forestry representative excavation or trenching as show on the plans cannot be done without unacceptable damage to trees to be protected, the Construction Engineer [John Fahrney, for this project] may request grading or alignment modifications to reduce damage to the tree.
  • Grading, excavation, and trenching near these trees shall be done under the supervision of an official forestry representative. 
  • Exposed roots shall be covered as soon as excavation and installation are complete.
  • Boring under a protected tree may be allowed.
  • The Engineer may elect to terminate lateral installation prior to conflict with tree.
  • Trees larger than 10” DBH* will be pruned by City Forestry to an approximate minimum height of fourteen (14) feet above the road wherever construction equipment is expected to invade the tree crown.  (Some limbs less than 14' high can be spared if noted in advance.)
  • Pruning to accommodate construction equipment invading the tree crown shall be done by the Contractor, under supervision by the Forestry representative.
  • All pruning shall be done according to ANSI A300 tree pruning specifications.
Bark abrasions
  • Contractor shall take precautions...not to disfigure, scar, or impair the health of any tree....
  • Contractor shall operate equipment in a manner as to not damage the branches. This may require using smaller equipment... and loading or unloading materials...away from trees....
  • Contractor shall notify City Forestry the same day of any damage to trees....
Soil compaction
  • No equipment or materials will be allowed to be parked on, or be piled on areas within five (5) feet a tree.
  • Construction traffic within 5 feet of a tree will be allowed only where necessary to complete grading, or sanitary sewer operations, at the discretion of the Construction Engineer.If the City Forester or City Engineer determines that a tree has been damaged due to failure to follow these specifications, or negligence of the Contractor or Subcontractor, a fine or liquidated damages shall be assessed to the Contractor or permit holder.  There is a schedule showing fines for each infraction.
Coordination between players is essential

In addition to the contractor, MG&E will be working on power lines, so they, as well as the contractor, have to sign off that they understand the new protections.  They have to work under supervision of the forestry representative.

So the forestry representative is a key player--let us hope he/she is present whenever endangered trees are at risk.

Likewise, the erosion control inspector, Tim Troester, is a key player, because of the vulnerability of this ravine to severe erosion during a big storm.

Success in saving the "endangered trees" depends on all players, including residents, working together.

*  Diameter at breast height

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