Middle St. Johns - Florida Department of Environmental Protection

266 Water Quality Assessment Report: Middle St. Johns
WBID
Waterbody
Segment Name
3001 Little
Econlockhatchee
River
3001 Little
Econlockhatchee
River
3001 Little
Econlockhatchee
River
3001 Little
Econlockhatchee
River
Waterbody
Type
Waterbody
Class
1998 303(d)
Parameters
of Concern
Parameters
Identified Using
the IWR
Proposed
Status
Stream 3F Biology Not
Impaired
Stream 3F BOD BOD Not
Impaired
Stream 3F Chromium3 Not
Impaired
Stream 3F Dissolved
Oxygen
Dissolved Oxygen Not
Impaired
Integrated
Report
Category 1
Priority
for
TMDL
Development
Projected
Year for
TMDL
Development
Comments 3
(# Exceedances/ # Samples)
PP= Planning Period VP= Verified
Period
2 Though biology was planning listed
due to a failed bioassessment in
1992, there are several passing
bioassessment scores in the verified
period (1996, 1999, 2000, and
2002) from which to conclude this
segment is not impaired for biology.
2 Delist. While BOD median is at
screening level (537 BOD values,
median 2.0 mg/l, range 0.1 - 20.4
mg/l), the DO is not impaired. BOD
data has shown an improving trend
in verified period. 80% of the BOD
values present in the verified period
are less than or equal to the MDL.
2
2 Delist. Dissolved oxygen is naturally
low, and bioassessment data
indicate that aquatic life use support
is being maintained (Passing
bioassessments in 1996, 1999,
2000 and 2002). Nutrients (TN and
TP) and BOD are all within
acceptable ranges. 348 TN values,
median 0.92 mg/l. 367 TP values,
median 0.09 mg/l. 537 BOD values,
median 2.0 mg/l. PP - 137/413
values below DO criterion. VP -
70/297 values below DO criterion.
656 DO values, median 5.8 mg/L,
mean 5.83 mg/L, range 0.17 - 61.3
mg/L. The dominant land use is
defined as urban (50%).