GENERAL46553 - Laserfiche WebLink

Home Browse Search

Task 1 Low Water Crossings The goal of this Task is to manage drainage of water on two of the of the old haul roads. In order to accomplish this, two (2) low water crossings are to be constructed within the Project Area, one on the Pit 4 Road, and one on the Pits 2 / 3 Road. The Pit 4 Road low water crossing will be constructed immediately above the first switchback located on this road. This crossing will serve to transport water from the north to the south side of the road, and into an existing drainage Swale. The other low water crossing will be constructed at the first switch back of the Pits 2l3 Road. This low water crossing will allow water to drain from the north to the south side of the road, moving the water into apre-existing drainage swale. PROJECT MANAGER will mark the location of each low water crossing in the field prior to construction beginning. Specifications The low water crossings shall be constructed to the specifications of Figure 1, Low Water Crossing. The crossings wiN be constructed at about athirty-degree (30 °) angle to the axis of the road, and will have a fall of five percent (5%) across the axis of each crossing. Ingress and egress routes shall be no steeper than 6H: 1V. The down hill slope of the crossings will be over filled to accommodate anticipated volumes of water passing through the low water crossings. The crossings shall be slightly longer than the width of the road above and below the crossing in order to capture water from the ditch above each crossing, and in order to allow the water io move into the pre-existing drainage swale below each crossing. Durable rock shall be placed at the base and on the sides of each crossing. The screened rack shall have an average size of two-inches (2"), shall be placed as a blanket throughout the length and width of the low water crossings. Durable rock rip rap shall be placed from the end of each low water crossing into the pre- existing drainage Swale for a distance of thirty feet (30') below the end of each crossing. The rock placed in the pre-existing Swale shall consist of two-inch (2") screened rock, overlain by clean four inch (4") rock. The rock shall be placed within these channels, which are approximately twelve inches (12") wide at the base, and onto the side slopes for an additional twelve inches (12") per side, as measured from the outside margin of the base of each channel. Durable rock is defined as rock material which gives off a ringing sound when struck with a hammer. Measurement and Payment Payment shall be made per low water crossing installed. Payment shall be made at the unit price established in the Bid Schedule, Item 1. The unit price bid will cover all costs for excavation, and rock placement per specifications. The price bid shall be considered full compensation for all equipment and materials necessary and incidental to completing the low water crossings to the specifications of this Task. Payment shall be as this Task is completed and approved by the PROJECT MANAGER.