|
|
Workshops
MODEL
SHOULDER/DITCHING SPECIFICATIONS
-
Shoulders will be lower and graded at a slightly
steeper cross-slope to provide positive drainage toward the ditch.
-
If possible, all inslopes will be no steeper than
2:1 (Horizontal to Vertical) and all backslopes will be no steeper
than 1:1.
- The depth of ditch should be at least 12” below the bottom
of the roadway gravel. If the depth of base gravel is unknown
then the ditch should be a minimum of 18” below the shoulder elevation.
Care should be given to avoid excessively deep ditches which could
create safety and liability concerns to motorists and/or pedestrians,
especially with steep side slopes.
- All ditches will be shaped with no hard transitions in slopes.
The shape should be rounded (parabolic) to minimize erosion and
water velocities. V-ditches should be avoided.
- The slope of the graded ditch should be a minimum of 1%. In
difficult situations, it should never be less than .5%.
-
No gravel of sod berm or windrow will be left in-between
the road and the ditch slope.
- Prior to any grading, the Contractor or Town will call Dig-Safe
toll-free number 1-888-DIG SAFE (344-7233) to protect against
possible damage. Comments like “I know there’s nothing there”
are not acceptable. The 72-hour waiting period will be adhered
to in ALL CASES, except emergencies.
- All work will be protected by proper work zone devices and procedures.
The standards presented in the latest edition of Part IV of the
Manual on Uniform Traffic Control Devices (MUTCD) will serve as
minimum standards.
- All culverts or obstructions will be flagged or marked prior
to grading to ensure no damage to the culverts or equipment.
- All “ditch spoils” will be properly disposed of by the operator
in accordance with all environmental considerations. An easement
will be obtained to dump excavated material onto private property.
- Any ditch drainage onto private property can only occur after
a drainage easement is on file with the Town.
- All work will be performed under the direction of the Road Commissioner
(Town Manager or Board of Selectmen).
- Any inconveniences to residents or to adjacent driveways shall
be avoided by prior notification.
- All culverts, geotextiles, and erosion control materials will
be approved of and/or bought by the Town for use.
- All unstable ditches and slopes will be properly protected against
erosion according to current best management practices and State
law.
|