K-15 
Table 1. Habitat classification for the Chesapeake Bay B-1 B1. 
Habitat Class 
Bottom Salinity (psu) 
Silt-clay (<62 p) content by 
Weight (%) 
1 . 
Tidal freshwater 
0-0.5 
N/A 
2. 
Oligohaline 
>0.5-5 
N/A 
3. 
Low mesohaliue 
>5-12 
N/A 
4-1. 
High mesohaline sand 
>12-18 
0-40 
4-2. 
High mesohaline mud 
>12-18 
>40 
5-1. 
Polyhaline sand 
>18 
0-40 
5-2. 
Polyhaline mud 
>18 
>40 
Table 2. Number of samples by habitat in the original index development data files used by Weisberg et al. (1997) and 
Alden et al. (2002). Calibration (Cal) and validation (Val) samples combined. Habitat Class designations as in 
Table 1. 
Habitat Class 
1 
2 
3 
4-1 
4-2 
5-1 
5-2 
Cal + Val 
Reference Degraded 
136 
92 
49 
5 
81 
7 
136 
Reference Good 
75 
32 
20 
14 
39 
39 
24 
appendix k 
2006 303(d) Assessment Methods for Chesapeake Bay Benthos 
