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The City of Atlanta plans to convert a recently acquired urban quarry into Bellwood Quarry Reservoir (BQR), an off-stream supplemental water supply. CE-QUAL-W2, Version 3.5, was used to perform five-year water quality simulations of the reservoir. Nine inflow/outflow design and operation scenarios were evaluated for thermal stratification, dissolved oxygen (DO), algae, and iron (Fe) and manganese (Mn). For a perpetual storage scenario with no inflow and outflow and an operating scenario with monthly pump exercising flows, the model predicts ample reservoir DO to maintain an oxidizing environment in the hypolimnion and low dissolved Fe and Mn. A single portal near the bottom of the reservoir is recommended for alternating pump exercise inflows and outflows. Continuous flow-through operating scenarios do not improve predicted water quality. However, if selected, a mid-depth inflow and bottom outflow design configuration is recommended. A natural monomictic cycle is essential to maintain hypolimnetic...

Geomembranes can provide an effective low permeability cover at many sites. Maintenance of overall stability is essential to design performance. The beneficial effects of textured geomembrane, drainage terraces and tensile geogrids are discussed. The use of both vegetative and non-vegetative covers to resist erosion is presented. The effects of construction equipment traffic, freezing, root growth and vermin on the geomembrane are also discussed. Finally, geomembrane penetrations and a closure concept which does not physically join the closure geomembrane to the bottom geomembrane are discussed.