Table V-8 (continued). Characterization of the Chesapeake Bay Program segments 
based on occupied quadrants in a plot of the 1 percent dis¬ 
solved oxygen concentration versus observed monthly mean 
dissolved oxygen concentration 1 . 
Number of Data Points By Quadrant by Designated Use 
CBP 
Segment 
Open- 
-Water 
1 
2 
3 
4 
BOHOH* 
39 
0 
0 
1 
ELKOH* 
39 
0 
0 
0 
SASOH* 
39 
0 
0 
1 
CHSOH* 
39 
0 
0 
1 
CHSMH 
37 
2 
1 
0 
EASMH 
39 
1 
0 
0 
CHOOH** 
34 
0 
0 
6 
CHOMH2** 
26 
2 
9 
3 
CHOMH1 ** 
33 
6 
1 
0 
LCHMH- 
4 
11 
24 
0 
FSBMH* 
36 
0 
0 
1 
NANTF** 
35 
0 
0 
5 
NANMH* 
38 
0 
0 
0 
WICMH 
28 
0 
0 
10 
MANMH* 
37 
0 
0 
1 
B1GMH* 
38 
0 
0 
0 
POCTF 
18 
0 
3 
19 
POCMH* 
40 
0 
0 
0 
TANMH** 
27 
6 
5 
1 
Deep-Water 
12 3 4 
12 8 14 1 
1 13 20 2 
Deep-Channel 
12 3 4 
2 0 3 0 
2 0 2 0 
'Quad 1: both 30-day mean and instantaneous minimum criteria achieved; quad 2: 30-day mean criterion 
achieved, instantaneous minimum criterion not achieved; quad 3: both 30-day mean and instantaneous minimum 
criteria not achieved; quad 4: 30-day mean criterion not achieved, instantaneous minimum criterion achieved. 
Based on data from the Chesapeake Bay Water Quality Monitoring Program twice monthly cruises between June 
and September, 1993 through 2002 (most recent 10 years). 
Single asterisk (*): Open-water use only segment with all data points in quadrant 1 and none or only one data 
point in the other three quadrants. 
Double asterisk (**): Open-water use only segment with a vast majority of data points (greater than two-thirds) 
in either quadrant 1 or quadrant 3. 
Single dash(-): Open-water use only segment with sufficient data points in quadrant 2 indicating a much higher 
occurrence where the 30-day mean criterion was achieved yet the instantaneous minimum criterion was not 
achieved. 
Boldface type: Open-water use only segment with a large number of data points in quadrant 1 and quadrant 4 and 
none or very few data points in the other two quadrants. 
Source: Chesapeake Bay Water Quality Monitoring Program database. 
http://www.chesapeakebay.net/data 
Guidance for Attainment Assessment of Instantaneous Minimum and 7-Day Mean Dissolved Oxygen Criteria 
