§ 8.3.3. Design criteria—General.

a.

All storm water conveyance facility design calculations shall be certified by a professional engineer currently registered in the State of Georgia.

b.

Methods to calculate storm water flows shall be in accordance with the Gwinnett County Storm Water Design Manual. The USGS method shall be used where applicable to check the magnitude of peak flows when other hydrologic methods recommended in the manual are used.

c.

All portions of a storm water conveyance system which drain areas falling within the same size category above shall be analyzed using the same methodology.

d.

Run-off coefficients used for the rational method and runoff curve numbers used for the SCS method shall be consistent with those shown in the Gwinnett County Storm Water Design Manual.

e.

Smooth interior corrugated polyethylene (PE) pipe shall not be used or installed under the road surface of existing or proposed to be dedicated public streets.

(Ord. of 6-28-2004(5))