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: September
11, 2007
SUBJECT: Weekly
Environmental Recommendation for Systems Operations
Recommendation
No
regulatory releases
to the south or estuaries are recommended.
Background
Daily afternoon thunderstorms decreasing by the end of
the week. A trough which
had been over the District the past two days has lifted north of the District
so expect shower coverage to drop down some today. An upper level low located near
The upper Kissimmee Basin received 0.85
inches of rainfall over the last 7 days to bring the 30-day total to 3.52 inches (52% of average) and the lower basin received 1.21
inches to bring the 30-day total to 4.36 inches (70% of average) (Daily Rainfall
Report for 09/10/07). Stages in
most of the upper basin lakes have been stable over the last seven days. Stage at S65C
headwaters has increased 0.5 feet in response to Kissimmee Division request to
raise the stage to 35 feet over the next several weeks.
Snail kites continue to nest on
Flow has been reestablished to the
According to the USACE
web site,
Monthly algal bloom monitoring was conducted on the
22nd of August. Four of the
10 monitoring sites were dry. An algal
bloom was present at 1 of remaining 6 survey locations. Algal toxins were not detected.
The September submerged-aquatic-vegetation (SAV) survey documented SAV at 80%
of the sites sampled. Several other
sites sampled in previous surveys were dry.
Water clarity was excellent at all sites. Results show that SAV
continues to recover following the hurricanes of 2004 and 2005, which removed
most of the SAV from the lake.
St. Lucie Estuary
No releases occurred at S-80 over the past
week. Weekly average salinities at the
four monitoring sites in the St. Lucie are given below in parts per thousand (ppt).
|
Weekly Average Salinity (ppt) |
|
|
Sampling Site |
Surface |
Bottom |
Envelope |
|
7.8 |
9.6 |
|
HR1 (N. Fork) |
11.7 |
14.2 |
|
|
16.4 |
17.2 |
8.0 25.0 |
A1A Bridge |
25.2 |
28.9 |
20.0 31.0 |
Average weekly salinity in the estuary increased
since the last report. Local freshwater
inflow continues to maintain surface salinity at both the
Caloosahatchee Estuary
During the past week, discharge at S-79 averaged
164 cfs.
Chloride concentration at the Olga Plant is presently 77 mg/l. Average salinity at the monitoring sites in
the upper Caloosahatchee Estuary decreased slightly over the past week. Data for specific sites are given below in
parts per thousand (ppt).
|
Weekly Average Salinity (ppt) |
|
Sampling Site |
Surface |
Bottom |
|
6.6 |
7.1 |
Rt. 31 Bridge |
NA |
7.7 |
I-75 Bridge |
5.8 |
9.8 |
|
8.0* |
NA |
|
19.6 |
21.0 |
Shell Point |
30.2 |
33.8 |
* based on two-day average.
Salinity in the upper estuary remains high for this
time of year. The 30-day average surface
salinity at
During the last sampling trip to the Caloosahatchee
at the end of August, a plankton bloom was noted upstream of S-79. FWRI reports that no Karenia brevis, the
Water Conservation Areas
On average, water levels are where they
were last week. WCA-3A
and 3B continue to have POOR inundation rates.
A maximum stage decrease of -0.10 ft for the
Rainfall was heavier last week than we have seen of late across
Everglades National Park (ENP) and
Salinity showed mixed trends across FL Bay last week. Salinity at Trout Ck. was flashy again last week,
ranging from 10 25 psu. Salinity in the Taylor ponds remained very
low for much of the week (~ 1 psu at Argyle Hendry, TR), with the exception of a flow reversal that pushed Bay
water up Taylor River and increased salinity to 10 15 psu
in the latter part of the week at Pond 5 (just downstream from station TR). Salinity
readings in the north-central Bay areas of
Water Supply
Water levels in the upper and lower
Six out of eleven water supply risk measures are in
the high risk category this week including the projected Lake O Stage (SSM), the Palm Index for Tributary Conditions, the LOK Multi-Seasonal Net Inflow Forecast and Lower East Coast
Service Areas 1, 2 and 3.
Water Conservation Areas 1, 2A continue to be in
the low risk category. Water
Conservation Area 3A changed from low to medium risk this week. The CPC Precipitation Outlook remains at
low risk this week, along with the LOK Seasonal Net
Inflow forecast.
WSE
(
The current
CC: George
Horne