Home Improvement Siding Kitchen Windows Vinyl Pools Patio Security 0172

Section 18 - Earthwork

When removing an existing structure which is to be replaced with a new structure, no

payment will be made under this item for the area occupied by the existing structure.

18-4 DITCH AND CHANNEL EXCAVATION

Ditch and channel excavation shall conform to Section 19-4, “Ditch Excavation”, of the State

Specifications, and these Specifications. Ditches and channels shall be excavated to line and

grade and sections as shown on the Plans. Material resulting from excavating ditches and

channels shall be used in fill and embankment areas as shown on the Plans.

18-4.02 Grade Control - Lined Channels

The Contractor shall place grade control points at twenty-five-foot (25’) intervals along the

invert of the shaped channel. For channels greater than twelve feet (12’) wide, the Contractor

shall place grade control points at twenty-five-foot (25’) intervals along each edge of the bottom.

Care shall be taken to prevent excavating below the channel grade line or beyond the slope

lines. Areas excavated below grade or beyond the slope shall be filled with suitable materials,

as determined by the Agency, and compacted to ninety percent (90%) relative compaction by

the Contractor at the Contractor’s expense.

18-4.03 Unsuitable Ditch and Channel Excavation and Backfill

Any unsuitable material encountered shall be removed and backfilled in accordance with

Section 18-5, “Unsuitable Material Excavation”, in this Section of these Specifications.

18-4.04 Unsuitable or Surplus Material Disposal

Unsuitable or surplus material excavated as channel excavation which, in the opinion of the

Agency, cannot be worked into the required embankments, shall become the property of the

Contractor and shall be disposed of as specified in Section 18-7, “Surplus Material Disposal”, in

this Section of these Specifications, unless otherwise specified in the Special Provisions.

18-4.05 Channel Backfill

In those areas where the bottom of the existing channel is below the proposed grade or

beyond the slope lines, the Contractor shall fill and compact these areas to a minimum 90

percent (90%) relative compaction with suitable material, as determined by the Agency. No

additional payment will be made for this work, as it shall be considered as included in the

Contract price for channel excavation.

18-4.06 Channel Embankments

Embankments shall be placed as shown on the Plans. Embankment areas shall be filled

with suitable material, as determined by the Agency, resulting from channel excavation. The fill

shall be placed in a neat and uniform manner, and shall be spread uniformly to the grades as

shown on the Plans. Where embankment is made on the existing channel or on other slopes,

the existing slope shall be plowed or cut into as the embankment is constructed so as to tie the

new embankment to the existing slope. All fill slopes shall be trimmed for a uniform

appearance. Fill areas in unlined channels shall be compacted to a minimum relative

compaction of ninety percent (90%), unless otherwise shown on the Plans.

In lined channels, fill areas shall be compacted to a minimum relative compaction of ninety

percent (90%) to an elevation one foot (1’) above the top of the channel lining, unless otherwise

Localized erosion, sloughing or other slight irregularities in the existing channel which may

occur between cross-sections, may not be shown on the Plans or cross-sections. Where the

localized erosion, sloughing or irregularities extend beyond the limits of the channel cross-

section, these areas shall be filled and compacted to conform to the design channel cross-

section. No additional payment will be made for these fills.