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: July 29, 2008
SUBJECT: Weekly
Environmental Recommendation for Systems Operations
Recommendation
No
Lake Okeechobee regulatory releases to
the south or estuaries are recommended.
Background
Some active thunderstorm days ahead.
Decent moisture and favorable upper level winds between a high pressure
area and an upper level low over the southeastern
Over the last seven days, the
upper Kissimmee Basin received 2.49 inches of rainfall to bring the 30 day
total to 8.19 inches (122% of average), and the lower basin received 2.64
inches to bring the 30 day total to 10.46 inches (168% of average).
Water levels continue to rise
in all of the upper basin lakes including
In the upper basin, snail
kites continue to nest on East Lake Toho,
Flow is approximately 300 cfs at S65 and 2000 cfs at S65C.
The water level
in the area of the restoration project decreases by 3.16 feet from 37.42 feet
near the middle of the restored reach (station KRBN) to 34.26 feet at the
downstream end (headwater stage at S-65C). A portion of the floodplain within the
restoration project is now inundated.
From 7/22/08 to 7/29/08
dissolved oxygen concentrations in the
According to the USACE web
site,
St. Lucie Estuary
There were no releases
through S-80 from C-44 over the past week. An average discharge of 80 cfs through S-48 from
C-23 and 234 cfs through S-49 from C-24 occurred over
the past week. 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 |
|
7.22 (6.48) |
8.08
(7.46) |
|
HR1 (N. Fork) |
5.31 (2.58) |
10.52 (9.51) |
|
|
9.70 (8.38) |
12.23 (11.40) |
8.0 – 25.0 |
A1A Bridge |
18.91
(16.95) |
25.61
(24.26) |
20.0 – 31.0 |
Compared with salinities of
the previous week, average salinity in the estuary increased about 0.5 to 2.7 ppt. Three of four
monitoring stations are reporting salinities within the preferred range. Salinity conditions in the estuary are
considered to be fair to good, based on the salinity preference of the oyster, Crassostrea virginica, and
location in the estuary.
Caloosahatchee Estuary
An average weekly discharge
of 1342 cfs occurred
at S-79. The concentration of chlorides
at the Olga Plant was 62 ppm Monday, 7/28, up from 54
ppm in the beginning of this reporting period. 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).
Based on the USGS flow meter
located just below S77 water is flowing back into the
|
Weekly Average Salinity
(ppt) |
|
Sampling Site |
Surface |
Bottom |
|
0.29 (0.43) |
0.29
(0.40) |
Rt. 31 Bridge |
NR (NR) |
NR (NR) |
I-75 Bridge |
0.41 (0.85) |
0.41
(1.10) |
|
1.18
(3.15) |
1.28
(3.55) |
|
6.81
(10.06) |
8.62
(10.43) |
Shell Point |
20.22
(28.76) |
22.29
(29.47) |
Compared with salinities of
the previous week, average salinity decreased throughout the estuary due to
local runoff. Average salinities dropped
between 0.11 ppt and 8.54 ppt
depending on location and depth. The 30 day average surface salinity is decreasing and
stands at 8 ppt. Salinity conditions in the upper
estuary east of
Background
concentrations of Karenia brevis, the
Water Conservation
Areas
Water levels
continue to rise in the
Rainfall totals were light to
moderate last week across Everglades National Park (ENP) and
Stages in ENP wetlands showed
mixed results, reflecting last week’s local rainfall patterns. Water levels dropped 1” in the panhandle
(station EVER6), and 2” at
Salinity trends across
Water Supply
Water levels in the upper and
lower
There was no change in the
water supply risk indicators since last week. Seven out of the eleven water supply risk
indicator parameters are now in the “low” risk category, including the CPC
Precipitation Outlook, Palmer Index for Tributary Conditions, the Lake
Okeechobee Seasonal and Multi-seasonal Net Inflow Forecast, and Water Conservation
Areas 1, 2A and 3A.
Three out the eleven water
supply risk indicators are now in the “medium” risk category, including LEC
Service Areas 1, 2 and 3.
Only one risk measure is now
in the “high” risk category - the projected Lake Okeechobee Stage (
LORS2008 (
The current
CC: George Horne