MEMORANDUM
TO: Chip
Merriam, Deputy Executive Director, Water Resources
FROM: SFWMD Staff Environmental Advisory Team
DATE: March 18, 2008
SUBJECT: Weekly
Environmental Recommendation for Systems Operations
Recommendation
No Lake Okeechobee regulatory releases to the
south or estuaries are recommended.
Background
Showers
returning early Thursday through Saturday. Breezy
southeast winds will bring a few light sprinkles to the east coast today but
otherwise dry conditions remain in place over the District with an old frontal
boundary to our south. Expect this front
to lift back north ahead of the next system Wednesday and allow some widely
scattered afternoon showers mainly east.
The next cold front will then move into central
Over the last seven days, the upper Kissimmee Basin received 0.25
inches of rainfall to bring the 30-day total to 3.62 inches (121% of average)
and the lower basin received 0.22 inches to bring the 30-day total to 3.36
inches (128% of average). Rainfall from
two weeks ago had caused water levels to rise (stage reversals) in all of the
lakes in the upper basin. These
reversals have ended and were approximately 0.1-0.2 ft.
The discharge from
A
whooping crane continues to nest on
Flow has been reestablished to the
Land
Stewardship will continue burning in Hickory Hammock and completed two upland
burns at
A
recommendation was made last week to modify the water level recession in Lake
Toho so that the water level in the lake would reach 53.5 feet at the same time
as the approved regulation schedule and then be lowered according to the
regulation schedule. This recommendation
was intended to address concerns raised by the U.S. Fish and Wildlife Service
about increased loss of snail kite nests in
On
Thursday March 13, 2007, U.S. Fish and Wildlife Service sent a request for a
deviation to the U.S. Army Corps of Engineers to hold the water levels in
According
to the USACE web site,
February
water-quality monitoring results are now available. Fourteen of the 25 monitoring stations had
sufficient water for sampling. Total P
averaged 152 ppb lakewide (compared to 240 ppb in
January) and 77 ppb at nearshore stations (compared
to 102 ppb in January). Total suspended
solids (TSS) averaged 54 ppm
lakewide (compared to 109 ppm
in January) and 26 ppm at nearshore stations (compared to 31 ppm
in January).
Reconnaissance
of the lake shoreline between Harney Pond and Clewiston last week revealed
extensive but patchy beds of Vallisneria
St. Lucie Estuary
There
were no releases through S-80 over the past week. A discharge of 46.86 cfs
occurred at S-97 on the C-23 Canal and there were no discharges at S-49 on the
C-24 canal. The current weekly average
salinities (in bold) at the four monitoring sites in the St. Lucie are given
below in parts per thousand (ppt), along with the
previous week’s (in parenthesis).
|
Weekly Average Salinity (ppt) |
|
|
Sampling Site |
Surface |
Bottom |
Envelope |
|
9.02 (10.30) |
10.88 (11.71) |
|
HR1 (N. Fork) |
12.53 (15.58) |
15.42 (16.76) |
|
|
16.57 (18.42) |
17.44 (18.62) |
8.0 – 25.0 |
A1A Bridge |
25.33 (26.30) |
27.89 (28.11) |
20.0 – 31.0 |
Average
salinity decreased during the past week throughout the estuary. Both the surface and bottom salinity are in
the preferred range at the
Caloosahatchee Estuary
Discharge
at S-79 over the past week averaged 110.29, an increase from the previous week
with 58.57 cfs.
The concentration of chlorides at the Olga Plant is 242 mg/l. Average salinity decreased by 4 ppt on the surface at Franklin Locks with a gradual
decrease at all sites moving down the estuary.
Weekly average salinities for specific sites are given below in parts
per thousand (ppt).
Current weekly averages (in bold) may be compared to last week’s data
(in parenthesis).
|
Weekly Average Salinity (ppt) |
|
Sampling Site |
Surface |
Bottom |
|
12.69 (16.68) |
13.31 (16.64) |
Rt.
31 Bridge |
14.27 (16.86) |
16.32 (17.73) |
I-75
Bridge |
15.91 (NA) |
18.65 (19.86) |
|
23.59 (23.11) |
23.81 (23.15) |
|
28.20 (30.53) |
30.52 (31.07) |
Shell
Point |
34.73 (34.86) |
35.67 (36.22) |
Salinity
at the
FWRI reports that no Karenia brevis, the
Water Conservation Areas
Water depths remain above one foot at many of the reported gages
and are above the optimum depths for wading bird foraging. However, there are good water depths and
recession rates in NW WCA-3A and good water depths
and fair recession rates in southern WCA-3B. It is still early in the nesting season and
it is hoped that these current hydrologic conditions we are experiencing for
most of the WCAs will have a minimum impact. Stages
in WCA-1 and WCA-2A remain
above regulation, and WCA-3 stages are right at the
bottom end of the E1 regulation schedule.
There have been some fires reported in WCA-3A
south of I-75.
Rainfall
across Everglades National Park (ENP) and
Data
problems persist with some of the ENP marine
platforms for salinity data. Salinity
concentrations remained generally stable or increased slightly last week at
stations in
Wildlife
We
had a tragic plane crash this last week where three FAU
graduate students were killed. They were
all part of a larger program to study bird foraging and nesting behaviors
within the Everglades and
Water Supply
Water
levels in the upper and lower
There
was no change in the Water Supply Risk indicators this week. Five out of eleven risk measures are in the
“high” risk category including the projected Lake Okeechobee Stage (SSM), the CPC Precipitation Outlook, and Lower East Coast
Service Areas 1, 2 and 3. The Palmer
Index for LOK Tributary Conditions improved from
“high” to “moderate” risk this week.
The
LOK Seasonal Net Inflow and the LOK
Multi-Seasonal Net Inflow Forecasts remain at “medium” risk this week.
Water Conservation Areas 1, 2A and 3A continue to be in the “low” risk
category.
WSE
(
The
current
CC: George
Horne