Town of Bradford,NH
Standards and Specifications for Upgrade of Existing Class VI Roads to Class V
Pursuant to RSA 231:8-33
Design Requirements:
1. The proposed highway improvement shall be submitted by way of a paper design developed by a licensed engineer and shall contain the following design data as a minimun:
(a) A profile showing both existing and proposed contours at 50 foot stations.
(b) Cross Sections showing both existing and proposed contours at 50 foot stations.
(c) Culvert sizes (length and diameter) and location, as well as bridges, catch basins and other devices shall be determined by the Road Agent after soliciting input form the licensed engineer for the project.
(d) Scale: Profile: 1” = 5’ Vertical
1” = 50” Horizontal
Cross Section 1” = 10’ Vertical
1” = 10’ Horizontal
Geometric Requirements:
1. Travel way width 20 feet minimum.
2. Shoulder width 2.0 feet minimum each side of travel way.
3. Maximum Slope of cuts and embankments – one vertical in three horizontal unless approved reinforcement or retainment is used.
4. Alignment grade Minimum: 1%; Maximum: 10%
5. Cross Slope of travel way”: ½” per foot – gravel surface; 3/8” per foot – asphalt surface treatment ( farmers mix ); ¼” per foot – asphalt surface treatment ( machine method, hot )
6. Cross slope of shoulder ½” to 5/8” per foot
7. Dead end roads to have either a 60” radius circle or a 50’ T head to act as a turnaround.
8. Guard Rail or natural retainage may be required at embankments.
When the original road layout or topography preclude meeting one or more of the above requirements, modifications can be approved, on appeal, by the Board of Selectmen in consideration with the Road Agent.
Construction Requirements:
1. Remove all topsoil, rubbish, and other yielding material and all tree stumps, brush, roots, boulders and like material from the full cross sections of the roadway to be constructed.
2. Scarify to minus two feet below base course to remove organic matter, large stones, etc.
3. Fill all holes and backfill area with clean bank run sand to roadway base course and compact well. ,
4. Provide 12” base course of clean bankrun gravel, compacted.
5. Provide 4” wear course of ¾” or 1 ½”crushed gravel, compacted.
6. Base fill, base course, and wear course to be shaped to meet geometric requirements.
7. Structures such as bridges, culverts, catch basins, etc., required for the proper construction of the roadway shall be provided and the area properly prepped to accept them.
8. Treat cuts and embankments for erosion control.
9. Install guard rails or natural retainage as required and standard signage for safe use of the road.
Construction standards shall be comparable to the best town road giving access to the road or portion thereof being reclassified.
Amended this 19th of October, 2004.
Board of Selectmen: Bruce Edwards, Chairman, Peter Fenton, Dave Pickman