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Brantner Ditch wa ~ will be conveyed to the ~uthern lake; some provision must be made at the lake to accept it with- out serious erosion. DRAINAGE AFTER RECLAMATION Flood Plain The flood plain and floodway limits ~~ill be modified during the mining process as described in the previous section. Final flood plain and floodway limits are shown on Plates I, II, and III. Uther modifications will resu]t. from other lake configurations. Changes in flood plain and floodway limits will not extend upstream or downstream of the project area. Additional flood storage may be created at the lake sites due to the excavation during she mining process. Increased flood storage will tc..~ to decrease flood F .ks for downstream reaches. Additional flood storage can be created if the scuth lake is sectioned off to create multiple water levels as described earlier. However, unless the project is designed specif',ally with flood storage in mind, attain- able flood storage 11 not have a measureable effect on the 100-year flood peak. Site Drainage Most of the mitiinq site south of Henderson Road will drain directly to the lake. The small over-flow structure at the north er~d of the lake will be provided although lake overflow will occur only during periods of high runoff. A small portion of the area north of Henderson Road will drain directly to the lake. No outlet for the north lake is re- quired. SUMMARY The mining and reclamation operation as planned will change the flood plain and floodway limits witkiin the pro- ject area. These changes ara identified cn Plates I, II, and III. Flood depths velocities and rates of flow will not be changed either upstream or downstream. The overbank portion of the 100-year flood will be allowed to pass with- out increasing the damage potential of existing facilities. All new facilities will b~ designed to minimize flood damage. -31