- Contract 6323 that the contractor signed with the City (#6323). These reinforce and add to what's in the "Standard Specifications." (see p. D-4)
- Standard Specifications for Public Works Projects, which outlines provisions that contractors have to adhere to in all projects. Tree protections were strengthened for this early 2010 revision of this document. (see p. 46)
In my next posting (above), I'll give a brief summary of all these details.
Tree protection in the contract
“The contractor is advised to review …the Standard Specifications for tree protection, which is new in 2010.”
“The intent of the design is to save as many trees as possible, and to minimize the damage to those trees that remain following construction. Trees that must be removed to complete the work are denoted on the plans with an X--most of these are to be inside the construction fencing (except those requiring removal for lateral installation). A few trees at the Owen Drive end within the construction fencing are to be saved, these trees shall be clearly marked to be saved in the field.
"The project corridor is heavily wooded. Because of the intent to save as many trees as possible, there are numerous trees to be saved that are just outside the construction limits, or adjacent to laterals. In many areas the temporary fencing will need to be placed immediately adjacent to a tree (not >5 feet away) in order to allow adequate space for the work.
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 a City of Madison Forestry Representative, or the City’s Arborist Consultant.
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. Exposed roots shall be covered as soon as excavation and installation are complete. The Contractor shall not rip or pull roots out towards the trunk of a tree while excavating with a backhoe. The use of a backhoe to cut roots is NOT acceptable.” ….
“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. Additional trees beyond those marked with an X on the plans may only be removed with the permission of the Construction Engineer and the Forestry representative.”
“…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.”
“…No equipment or materials will be allowed to be parked on, or piled on areas within 5 feet of 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.” Source
Tree protection in the Standard Specifications
"These specifications shall be applicable to all Contractors working in the Public Right of Way, whether by permit, Public Works Contract, Developer Agreement or any other permission to work within the Public Right of Way. However, any Contractor doing work related to an emergency situation as described in Sections 10.05(13)(a) and 10.101(5) of the Madison General Ordinances are not bound by these provisions for those situations only." ...."The maintenance and enhancement of the urban forest is a goal of the City of Madison. Preserving and protecting healthy trees is one objective towards achieving this goal. Trees vary in their ability to adapt to altered growing conditions. Mature trees have established systems in the pre-existing physical environment. Disruption of this environment by construction activities interrupts the tree’s physiological processes causing depletion of energy reserves and a decline in vigor, often resulting in the tree’s death.
These tree protection specifications are intended to insure that appropriate practices will be implemented in the construction phase of the project to protect a tree’s structural integrity and future health. Also, these specifications will reduce the likelihood of undesirable consequences that may result from uninformed or careless construction practices adjacent to trees.
The three most common forms of construction damage to trees are:
- Root cutting
- Bark abrasions
- Soil compaction
In particularly sensitive areas or areas of dense tree cover, the City Engineer may elect to specify the use of a protective fencing to mark the tree protection zones or zones of no disturbance. Whenever construction fencing is used, a bid item shall be included in the contract, unless specified as incidental.
107.13(a) Underground Utility Excavation & Installation.
The Contractor shall not grade, excavate, or otherwise disturb the area within five (5) feet of any tree as measured from the outside edge of the tree at DBH (Diameter at Breast Height) along the length of the terrace, without prior permission from the City Forestry Representative.
For laterals or utilities that are in close proximity to terrace trees, the situation shall be reviewed on a case by case basis by the Engineer and City Forestry Representative. The contractor shall use construction methods to minimize tree damage as directed by the Engineer. The Engineer may elect to terminate lateral installation prior to conflict with tree (normally terminate at the curb). Most laterals shall have their locations verified and on the plan set in advance of bidding. Laterals that have not had their locations verified, shall be so noted on the plans.
Boring under or within the 5 foot protection zone may be allowable.
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. Cuts may be made with an ax, lopping shears, chainsaw, stump grinder, or other means which will produce a clean cut. Exposed roots should be covered as soon as excavation and installation are complete.
The Contractor shall not rip or pull roots out towards the trunk of a tree while excavating with a backhoe. The use of a backhoe to cut roots is NOT acceptable."
107.13(f) Bark Abrasions and Limb Damage.
"Contractor shall take precautions during construction not to disfigure, scar, or impair the health of any tree on public or private property.
Pre-construction pruning – 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. All pruning shall be done according to ANSI A300 tree pruning specifications. Occasionally a limb may have to remain at a height less than fourteen (14) feet above the roadway. These instances shall be noted during the ‘walk thru’ and the Contractor shall employ methods to protect said limb. Contractor shall operate equipment in a manner as to not damage the branches of a tree. This may require using smaller equipment and loading or unloading materials in a designated space away from trees on the construction site.
Contractor shall notify City Forestry the same day of any damage to trees resulting from construction activities.
107.14(g) Soil Compaction.
No equipment or materials will be allowed to be parked on, driven over, or be piled on areas within five (5) feet a tree. This not only prevents compaction, but also prevents damage to the trunks of trees and branches through scraping of scuffing the bark.
107.14(h) Contractor / Foreperson Acknowledgement.
The Tree Protection Specification and known conflicts and concerns shall be reviewed at the Pre-Construction meeting with the Contractor. This review shall include review of a one page educational informational sheet that details the procedures for avoiding damage to the tree and tree roots. The Contractor’s representative shall sign the acknowledgement prior to start of construction.
Utilities or others working in the Public Right of Way shall be required to sign this acknowledgement on a case by case basis.
107.14(i) Cost Recovery Charges and Liquidated Damages.
The Contractor’s failure to follow the proper safeguards of these specifications shall result in the following cost recovery charges and liquidated damages to be assessed against the Contractor:
Where construction damage occurs causing or resulting in removal of the tree:
1. The costs associated with removing the tree including wood disposal.
2. The costs associated with removing the stump to a depth of at least 24 inches below the ground.
3. The costs associated with replanting a replacement tree that is balled & burlapped and shall have a minimum caliper of three (3) inches. The species and replanting location shall be determined by City Forestry.
4. The value of the existing tree which shall equal $125.00 per trunk diameter inch, measured at 4.5 feet above the ground.
For bark scraping and broken branches:
1. The costs associated with pruning broken branches, including wood disposal.
2. Loss of limb or broken branch larger than three (3) inches in diameter: $150.00 for each occurrence. Breakage of limbs that are less than fourteen (14) feet above the roadway shall be reviewed on a case by case basis.
3. Damage to trunk or bark larger than one square foot in area: $400.00 each area.
For root cutting or excavation within the root protection zone:
1. For mechanical excavation within five (5) feet of a tree, along the length of the terrace or sidewalk side of the tree, including ripping of roots back towards the trunk, without prior permission from City Forestry Representative: $150.00 for each occurrence
2. For mechanical excavation beyond six (6) inches or one (1) foot of the proposed curb installation, as determined by the size of existing tree and terrace width, including ripping of roots back towards the trunk: $150.00 for each occurrence (see Curb excavation and installation specifications).
For Public Works Contracts these charges and liquidated damages shall be assessed as Liquidated Damages. For Private Contracts, Permit work, or others, these charges and liquidated damages shall be assessed as City imposed forfeitures or private contract forfeitures.