3. Spoil banks should not exceed plus one-half foot MSL in 

 elevation and should be lower where possible. 



4. Openings in spoil banks should be maintained at predetermined 

 intervals in order to allow free passage of water, nutrients, 

 and aquatic life between the marshland and the channels. 



5. The construction of impoundments should be limited. Impound- 

 ments decrease flooding and increase evaporation and temperatures, 

 resulting in an adverse change in environment for various biota. 



6. In some situations in order to retard erosion of spoil banks 

 and subsequent filling of channels, stabilization by riprap or 

 vegetation may be considered. 



7. Care should be taken to avoid dredging during wildlife migrations, 

 spawning, and nesting times. 



8. The seaward ends of canals should be plugged until excavation 



is complete. Where canals cross a bayou, the ends emptying into 

 the bayou should be plugged. 



9. Spoil from dredging should be disposed of in some predetermined 

 manner based upon the environmental situation under consideration. 

 Options range from local to (if feasible) deep and open-water 

 disposal . 



10. Spoil can be used in certain activities to advantage. For 

 instance, dredged material may be used to nourish beaches or to 

 control the erosion of river banks. Under some circumstances 

 it can be used to stabilize estuarine lake and bay shores. 



11. Upon abandonment of an area, the levees should be removed in 

 order to try to restore the area to its former condition. 



4.7.3 Excavation for Fill 



Many artificial waterways are created primarily to obtain fill to 

 raise the land surface of low-lying coastal areas. When this type of 

 site development occurs, the borrow areas may be fashioned into lakes or 

 boat canals to provide extra benefits. Such projects may have serious 

 ecological effects. 



Waterfront housing developed by dredging coastal systems and using 

 the dredged material to fill and elevate the land may be very damaging 

 to natural resources, particularly when the dredge spoil is piled on 

 adjacent wetlands or low lands to gain elevation and to create lots for 

 canal side homes. Such projects affect the ecosystem adversely in three 

 major areas: (1) water quality, (2) habitat, and (3) ecosystem productivity. 



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