Projects

Cobb County, GA

Description:
Noonday Creek is located in a highly urbanized portion of Cobb County with a drainage basin in excess of 14 square miles. In an effort to reduce downstream flooding during the smaller storm events and alleviate ongoing channel degradation, Cobb County is planning to construct a regional stormwater management facility across the creek in the Chastain Meadows area.

Florence & Hutcheson Services:
Florence & Hutcheson was initially selected by Cobb County to provide On-Call Services associated with the redesign of this unique structure due to our familiarity with the design and installation of articulated concrete block mats for use as overtopping protection. The services associated with this contract included peer review of the proposed dam and spillway design, DAMBRK modeling and inundation mapping, and Georgia Safe Dams Program coordination.

Subsequently, Florence & Hutcheson was on the team selected by Cobb County to provide design and evaluation services of the new facility. These services included soil borings, materials testing, spillway analysis, embankment design, seepage drain layout and configuration, design and layout of the articulated concrete block mats, realignment of the existing 30 inch sanitary sewer outfall, preparation of construction documents, bidding, and construction administration.

The principal spillway of the dam will consist of a quad 10’ x 11’ concrete box culvert with a rectangular weir box sized to reduce the flows during the lower storm events. The embankment is currently designed to overtop during large storm events. Overtopping protection will be provided by tapered articulated concrete block mats.