*.••• P.C. 



Figure 2. Structural measures installed in the TLT mitigation bank area. 



depending on prevailing hydrological conditions and desired management results. A flap gate has 

 also been installed on the weir, which can be closed to prevent highly saline water from entering 

 the management area. This weir has been designed to insure the ingress and egress of marine 

 organisms. During the intensive management period, TLT has agreed to construct the additional 

 weir if a majority of the cooperating agencies determine the need for one along the southern end 

 of the mitigation area. 



METHODS AND MATERIALS 



To evaluate the effectiveness of the management plan, a monitoring program is being conducted 

 to gather and assimilate information inside and outside of the area concerning vegetative 

 community changes, water salinity, tide fluctuations, change occurring to the land:water ratios, and 

 trapping and hunting harvests. 



Historical Change Assessment 



A historical change assessment of the land:water ratio has been prepared to show the cumulative 

 impacts over time of natural subsidence, erosion, compaction, and saltwater intrusion. Five sets of 

 aerial photographs (1953, 1971, 1980, 1983, and 1985) were used for comparison. The area of land 

 and water was determined by planimetry for each of the 5 years. 



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