Farrah (Orange County)
Florida LAKEWATCH Water Chemistry Summary
Location: Latitude 28°30'30", Longitude 81°19'16"
Period of record: 60 sampling dates; February 4, 1991 to December 10, 1999
Surface area (Shafer et al. 1986): 8 acres / 3 hectacres
Lake Region (Griffith et al. 1997): Orlando Ridge
Geologic formation (Brooks 1981):
The geology is dominated by phosphatic sand, silty sand, and clay of the Hawthorne Formation.
Physiographic region (Brooks 1981):
The water body lies in the Orlando Promontory division of the Central Lake District.
Supplemental, unpublished water chemistry data, University of Florida.
Numbers reported below are the average for 3 months sampled:
|
pH |
8.1 |
Sulfate (mg/L) |
56.9 |
|
Total alkalinity (mg/L as CaCO3) |
28.0 |
Calcium (mg/L) |
22.8 |
|
Conductance (µS/cm @ 25 °C) |
258 |
Magnesium (mg/L) |
7.0 |
|
Color (Pt-Co units) |
8 |
Sodium (mg/L) |
9.0 |
|
Chloride (mg/L) |
18.3 |
Potassium (mg/L) |
10.0 |
|
Silicon (mg/L) |
0.5 |
|
|
Long-term Florida LAKEWATCH Data
Numbers reported below are the minimum, average, and maximum value for the 60 months sampled:
|
|
Minimum |
Average |
Maximum |
|
Long-term total phosphorus concentrations (µg/L) |
10 |
20 |
40 |
|
Long-term total nitrogen concentrations (µg/L) |
360 |
810 |
1850 |
|
Long-term total chlorophyll concentrations (µg/L) |
3.0 |
11.0 |
29.0 |
|
Long-term Secchi depth (ft) |
3.3 |
6.8 |
13.8 |
1999 Florida LAKEWATCH Data
Numbers reported below are monthly averages calculated from 3 stations for total phosphorus (TP, µg/L), total nitrogen (TN, µg/L), chlorophyll (CHL, µg/L) and Secchi depth (SECCHI, ft) during 1999:
|
Date |
TP (µg/L) |
TN (µg/L) |
CHL (µg/L) |
SECCHI (ft |
|
Jan-08-99 |
18 |
1050 |
7.7 |
7.0 |
|
Feb-10-99 |
19 |
1040 |
13.3 |
6.5 |
|
Mar-11-99 |
21 |
910 |
6.3 |
9.0 |
|
Apr-02-99 |
22 |
760 |
10.0 |
5.0 |
|
May-14-99 |
18 |
400 |
6.7 |
5.5 |
|
Jun-08-99 |
17 |
570 |
6.7 |
6.5 |
|
Jul-09-99 |
13 |
370 |
5.7 |
6.0 |
|
Aug-14-99 |
14 |
460 |
7.7 |
5.8 |
|
Sep-05-99 |
14 |
450 |
6.7 |
5.5 |
|
Oct-02-99 |
14 |
610 |
10.0 |
5.5 |
|
Oct-31-99 |
11 |
910 |
5.3 |
7.0 |
|
Dec-10-99 |
12 |
1260 |
6.0 |
7.3 |
|
|
|
|
|
|
|
1999 Average |
16 |
730 |
7.7 |
6.4 |
Farrah (Orange County)
Florida LAKEWATCH Aquatic Plant Summary
Aquatic plant data collected on June 22, 1993
|
Percent area covered with aquatic vegetation (PAC, %) |
36 |
|
Percent of lake's volume filled with vegetation (PVI, %) |
4 |
|
Average emergent plant biomass (kg wet wt/m2) |
4.9 |
|
Average floating-leaved plant biomass (kg wet wt/m2) |
0.5 |
|
Average submersed plant biomass (kg wet wt/m2) |
3.4 |
|
Average width of emergent and floating-leaved zone (ft.) |
11 |
|
Average lake depth (m) |
4 |
Frequency that plant species occur in 10 evenly spaced transects around the lake.
|
Common Name |
Plant Species |
Frequency (%) |
|
southern naiad |
Najas guadalupensis |
90 |
|
torpedograss |
Panicum repens |
70 |
|
cat-tail |
Typha spp. |
60 |
|
water-pennywort |
Hydrocotyle umbellata |
40 |
|
water primrose |
Ludwigia octovalvis |
40 |
|
spatterdock |
Nuphar luteum |
20 |
|
pickerelweed |
Pontederia cordata |
20 |
|
giant bulrush |
Scirpus californicus |
20 |
|
duck-potato |
Sagittaria lancifolia |
10 |
|
smartweed |
Polygonum hydropiperoides |
10 |
|
willow |
Salix spp. |
10 |
|
green algae |
Chlorphyta |
10 |