2.7.8. Deep Creek

2.7.8.1. About Deep Creek

Figure 2.33
Figure 2.35 The Deep Creek Tributary (WBID 2549 and 2589).
  • East of the St. Johns at Palatka
  • Primary Land Use: Forested, Row Crop Agriculture
  • Current TMDL reports: Dissolved Oxygen – 2589
  • Verified Impaired 2016 (final): Iron (2589 med)
  • WBID Area: 60.5 sq. mi.
  • Beneficial Use: Class III F (Recreational – Freshwater)

2.7.8.2. Data sources

Data were downloaded from the FL STORET and WIN websites (DEP 2010f, NEW DEP 2018) and filtered based on the stations (DEP 2010g) in Deep Creek WBIDs 2549 and 2589 (DEP 2014c) shown above. The filtered dataset was used to generate Table 2.9.

2.7.8.3. Discussion

Water quality data for Deep Creek are shown in Table 2.9. Deep Creek is a tributary of the LSJR that drains the eastern banks around Hastings and Spuds, and thus receives substantial agricultural inputs, such as nutrients. Historical concentrations of total nitrogen were elevated but not above the recently updated WQC (DEP 2015c; DEP 2016e; DEP 2016k), but recent data regarding nitrogen concentrations in the Deep Creek watershed are not available in STORET.  Levels of total phosphorus were significantly above the recommended WQC (Figure 2.31). Non-point source rainwater runoff is likely the major cause of the elevated nitrogen/phosphorus concentrations in this area. Chlorophyll-a has been removed from the recent verified impaired list, as the annual geometric mean chlorophyll-a concentrations have not exceeded the WQC (20 μg/L) more than once over the past three years, but there appears to be an increasing trend in chlorophyll-a concentrations.

In addition to nutrients, organic matter, temperature, and community structure (i.e., number and types of plants and animal species), among other biotic factors, may contribute to the lower dissolved oxygen concentrations in these tributaries. As a consequence of the above factors/conditions, a TMDL report for dissolved oxygen was published in 2009 (Magley 2009d) for WBID 2589 (Sixteen Mile Creek). Elevated concentrations of cadmium, copper, nickel, and silver were measured previously in Deep Creek, as compared to the Class III WQC for metals. Recent data indicate that these concentrations have remained below the WQC, but metal concentrations increased in 2018 compared to 2016 and 2017.

No recent measurements were available in WIN or STORET from 2016 to 2018 for the following parameters:

  • Fecal Coliform

Historical water quality data for Deep Creek are available in previous versions of the River Report.

Table 2.9 Water quality data for Deep Creek.

 Water QualityAverage and Number of Samples º
ParameterCriteria (FW)201620172018
Dissolved Oxygen (mg/L)≥34% sat. (≥3.0)4.13
(8 of 17 samples)
4.65
(2 of 9 samples)
4.98
(1 of 9 samples)
Total Nitrogen (mg/L)<1.541.00
(1 of 16 samples)
3.46
(2 of 10 samples)
0.96
(0 of 2 samples)
Total Phosphorus (mg/L)<0.120.27
(26 of 34 samples)
0.22
(11 of 17 samples)
0.18
(10 of 17 samples)
Chlorophyll-a (µg/L)<203.11
(0 of 17 samples)
7.86
(1 of 9 samples)
8.67
(1 of 9 samples)
Arsenic (µg/L)≤501.03
(0 of 17 samples)
0.72
(0 of 8 samples)
2.13
(0 of 8 samples)
Cadmium (µg/L)≤0.30.01
(0 of 17 samples)
0.07
(0 of 8 samples)
0.09
(1 of 8 samples)
Copper (µg/L)≤9.31.21
(0 of 17 samples)
1.06
(0 of 8 samples)
2.44
(0 of 8 samples)
Lead (µg/L)≤3.2Not availableNot available0.50
(0 of 8 samples)
Nickel (µg/L)≤520.43
(0 of 17 samples)
0.46
(0 of 8 samples)
1.19
(0 of 8 samples)
Silver (µg/L)≤0.070.00
(0 of 17 samples)
0.01
(1 of 8 samples)
0.06
(1 of 8 samples)
Zinc (µg/L)≤1209.01
(0 of 17 samples)
7.56
(0 of 8 samples)
11.88
(0 of 8 samples)
Turbidity (NTU)<29Not availableNot available8.64
(0 of 9 samples)
Note: Hardness-dependent freshwater criteria for cadmium, copper, lead, nickel, and zinc were generated based on a hardness concentration of 100 mg/L.
° = Number of samples below Water Quality Criteria for Dissolved Oxygen; Number of samples above Water Quality Criteria for all other parameters.
FW = freshwater; SW = saltwater (marine). Values denoted with (*) indicate a proposed criterion, which has not yet been adopted.
Values denoted with (‡) are reference values based on EPA criteria (EPA 2010b), but the water body is not regulated by this standard.