36 



The depth soundings collected during this video transect indicated the western side of 

 the borrow pit sloped down into a small basin composed primarily of silt. This flat region 

 displayed a depth of 9 m before depths gradually decreased in association with the presence 

 of the dredged material feature. The depth values within the borrow pit as indicated on the 

 NOAA chart for New Haven Harbor suggest the water column along Transect F was deeper 

 at one time (Figure 3-14). Extrapolating from the NOAA soundings, a potential area of 

 recent dredged material accumulation was identified in the basin and over the apex of a 

 shallow area (originally 24 ft). Based on the reported disposal volume, narrow configuration 

 of the borrow pit, and relatively shallow water depths, a dredged material deposit ranging in 

 thickness from 0.5 to 1.5 m is possible. 



Two additional transects (one longitudinal and one transverse) were occupied and 

 results overlaid on the data from Transects A, B, C, D, and F (Figure 3-15). In general, 

 strong agreement was observed in the classification of sediment along the margins and 

 within the northern portion of the borrow pit. The surface sediment distribution within the 

 southern portion of the borrow pit appeared more heterogeneous as differences in sediment 

 classification were noted on several overlapping, or closely spaced tracklines (i.e. Transects 

 A and F). This disagreement is likely the result of the chaotic nature of the dredged material 

 and the many small patches of fine sand, silt, and shell on the surface of the deposit. 



3.3.2 Benthic Macrofauna 



The macrofauna encountered during the towed video survey included horseshoe crabs 

 {Limulus polyphemus), sea stars {Asterias sp.). Common Oysters {Crassostrea virginica), as 

 well as active mussel beds, and various finfish. The bivalves and sea stars were found 

 inhabiting the walls of the pit, as well as concentrated in the areas outside the pit. The 

 horseshoe crabs and finfish were found foraging in the silt deposits within the borrow pit. 

 Macrophytic algae (mainly Ulva) were detected in small clumps along several survey lines 

 (Figure 3-15). However, there was no discemable pattern in spatial distribution. 



Monitoring Cruise at the Morris Cove Borrow Pit 



