§ 8.4. Surface drainage.

8.4.1 Design standards.

1)

All new proposed channels shall be designed to carry at least the 100-year storm with one foot of freeboard.

2)

Transition channels shall be provided at the inlet and outlet ends of all culverts and pipe systems, unless otherwise provided herein.

3)

The maximum flow velocity at the project site's downstream property line shall not exceed the pre-developed velocity.

4)

In cases of potential erosion due to irregular channel alignment, extreme velocities, or excessive slopes, a paved ditch shall be required, unless otherwise directed by the community development department.

5)

The cross-sectional shape of channels shall be as found in the Manual for Erosion and Sediment Control in Georgia. "V" shaped cross-sections are not permitted in grassed channels.

6)

If the channel will be affected by backwater from culverts, bridges, other structures or floodplains, backwater elevations shall be shown in profiles of the channel.

8.4.2 Construction standards.

1)

The channel shall be shaped to the dimensions specified on the approved plans and shall be free of overfalls, gullies or other irregularities.

2)

Channels in fills shall be lined.

3)

Protective cover in grassed channels shall be installed as soon as the earthwork is completed.