M E M
O R A N D U M
TO: Chip
Merriam, Deputy Executive Director, Water Resources
FROM: SFWMD Staff
Environmental Advisory Team
DATE: April
28, 2009
SUBJECT: Weekly Environmental Conditions for Systems
Operations
Summary
Discharge from
Background
Mostly
dry for the next week. High pressure
over the area will limit shower development the next few days. Breezy southeast winds will bring some light
showers south and south east. There is
the potential for some scattered afternoon shower activity this weekend. The next ten days precipitation outlook is
below average with moderate confidence.
Over the last seven days, the upper Kissimmee Basin received 0.02
inches of rainfall and the lower Kissimmee Basin received 0.05 inches (Daily
Rainfall Report 4/27/09). Stage in Lakes
Kissimmee, Hatchineha and
Discharge from East Lake Tohopekaliga and
Snail kites continue to nest
on
Discharge from
A
slight turbidity plume (presumably from the ongoing construction) is visible in
lower Pool B/C and northern Pool D. Discharge at S65C is about 200 cfs.
Over the last seven days, dissolved
oxygen (DO) concentrations in the
According to the USACE web
site,
An apple snail
mark-recapture experiment is being conducted on the lake to assist in the
development of methods for large-scale snail stock enhancements. Last
Wednesday, Okeechobee Division staff tagged 1500 adult apple snails obtained
from the District-funded snail-rearing facility at Harbor Branch Oceanographic
Institute. The following day, the snails were released in
Saint Lucie Estuary
Over the past week, no
discharge occurred at S-80. Discharge
from the
|
Weekly Average Salinity
(ppt) |
|
|
Sampling Site |
Surface |
Bottom |
Envelope |
|
20.7 (20.5) |
21.9 (21.5) |
|
HR1 (N. Fork) |
25.3 (24.8)
|
26.3 (25.7) |
|
|
27.6 (27.3) |
27.6 (27.5) |
8.0 – 25.0 |
A1A Bridge |
31.3 (31.6) |
33.2 (33.4) |
20.0 – 31.0 |
Salinity throughout the
estuary increased slightly last week, except at A1A Bridge which had a slight
decrease. At both the Roosevelt and A1A
Bridges, weekly average salinity is slightly above the upper bound of the
preferred range. Salinity conditions in
the estuary are considered to be fair considering the time of year, the
location in the estuary, and salinity preference of the oyster, Crassostrea virginica.
Caloosahatchee Estuary
During the past week, no
discharge occurred at S-79. Discharge
averaged 128 cfs at S-78, while discharge at S-77 was
unavailable. The concentration of
chlorides at the Olga Plant was 157 ppm on Sunday. The current weekly average salinities (in
bold) at the six monitoring sites in the Caloosahatchee Estuary are given below
in parts per thousand (ppt), along with the previous
week’s (in parenthesis).
Weekly Average Salinity
(ppt) |
||
Sampling Site |
Surface |
Bottom |
|
NR (5.3) |
9.1 (6.4) |
Rt. 31 Bridge |
8.5 (5.3) |
9.1 (7.0) |
I-75 Bridge |
9.6 (6.0) |
11.4 (9.6) |
|
17.1 (14.8) |
17.9 (18.5) |
|
24.7 (24.7) |
25.6 (25.2) |
Shell Point |
34.7 (34.1) |
34.8 (34.5) |
Average salinity increased
throughout the estuary. Conditions in
the upper estuary east of
Fish and Wildlife
Research Institute reports that water samples collected alongshore between
Pinellas and Monroe counties contained no K.
brevis.
Monitoring data collected by the River, Estuary and Coastal Observing
Network (RECON) of Sanibel-Captiva Conservation
Foundation (SCCF) indicated dissolved oxygen concentration at Fort Myers and
Shell Point ranged from 5.2 to 7.5 mg/L and chlorophyll at Fort Myers and Shell
Point ranged from 1.0 to 16.0 mg/L.
Water Conservation
Areas
The high rate of
pan evaporation (1.80 inches), continues to draw down water levels, which are declining at rates considered fair or good for
wading birds throughout the WCAs, but were particularly high in WCA-2A and -3A,
-0.30 and -0.28 foot, respectively, last week. WCA-2A is dry.
Stage Change: WCA-1: -0.17 foot WCA-3A: -
0.28 foot
WCA-2A: -0.30 foot WCA-3B: - 0.15 foot
WCA-2B: -0.18 foot NESRS: - 0.03 foot
All WCAs remain far below their regulation schedules. The
WCA-1 marsh is about -0.5 foot below, WCA-2A canal stage has dropped to about
-1.4 feet below, and the WCA-3A marsh is about -0.5 foot below Zone E1.
Twenty gauges in Big Cypress,
the WCAs, and in
Water depths are below ground
in much of the Greater Everglades. Except
for coastal areas, ENP is dry, with soil water depths well below -1 foot in
most of the Park. Water depths -1 foot or below exist in WCA-2A and the
northern half of WCA-3A. Surface water remains only in parts of WCA-1,
WCA-2B, southern WCA-3A, and WCA-3B.
The driest areas of the WCAs are now in the high risk category for muck fires, and
most of the Greater Everglades at moderate risk. The wetter sections of
WCA-1, WCA-2A, and WCA-3A and -3B, and coastal ENP are still in the low muck
fire risk category.
Wading bird feeding conditions
remain good in parts of WCA-1, -3A, and -3B.
The rest of the Greater Everglades are too dry, with a few areas still
too deep for feeding. With continuing high evaporation rates, these areas
will continue to provide for future foraging for a while.
Light rain fell across ENP
and
Stages continued to drop last
week. Water levels in Shark River Slough
and at the
Salinity was mostly steady or
increasing in
Water Supply
Groundwater levels across the
District continue to decline. Floridan aquifer wells in the
Water supply risk indicators
in the "low" risk category include the LOK Seasonal Net Inflow
Forecast and the LOK Multi-Seasonal Net Inflow Forecast. The Palmer Index for LOK Tributary Conditions
is in the “high” risk category this week. The CPC Precipitation Outlook, the
projected LOK Stage for the next two months, and WCA 1 continue in the
"medium" risk category. Water
Conservation Area 3A has moved into the "medium' risk category this week
as well.
The water supply risk
indicator for Service Areas 1 and 2 in the LEC is in the "medium"
risk category, with two days per week watering restrictions in place except for
the utilities at risk. Service Area 3 in
the LEC has moved into the “high” risk category because of dry conditions in
south Miami-Dade. Water Conservation Area 2A remains in the "high"
risk category, with headwater elevation at S11B below Line 2 (9.64 feet).
LORS2008 (
Stages in
CC: George Horne