Underdrain Trench System

1. Lay out and mark all areas of repair.

2. Excavate area to be repaired to a minimum depth of ” below bottom of repair or below other surface material and to a width of ”.

3. Install a layer of support fabric around complete perimeter of drain area leaving adequate material to wrap top of drain area to prevent contamination of drain.

4. Install stone aggregate in drain area and wrap with support fabric.

5. Install perforated pipe when necessary.

6. Where new underdrain system intersects existing structure or storm sewer line, tie into existing system to allow drainage of underdrain system. Provision shall be made to drain system where no structure or storm line exists.

7. Install specified finish.