M E M O R A N D U M
TO:
Ken Ammon, Deputy Executive Director
Tommy Strowd, Assistant Deputy Executive Director
Terrie Bates, Assistant Deputy Executive Director
FROM:
SFWMD Staff Environmental Advisory Team
DATE:
November 3, 2009
SUBJECT:
Weekly Environmental Conditions for Systems Operations
Summary
Discharge
from Lake Kissimmee is currently 234 cfs. Lake
Okeechobee stage is 14.04 feet NGVD, which is 0.10 foot lower than a week ago,
0.44 foot lower than a month ago, 0.71 foot lower than it was a year ago, and
0.08 foot above the simulated average using the current regulation
schedule. Salinity conditions in the Saint Lucie estuary are considered
to be good based on the salinity preference of the oyster, Crassostrea
virginica, and location in the estuary. In
the Caloosahatchee Estuary, salinity conditions are good in the upper estuary,
and good in the lower estuary. The week’s pan
evaporation was 1.22 inches this week. Groundwater levels across
the District are slowly declining.
The
United States Army Corps of Engineers (USACE) 8-day pulse releases to the
Caloosahatchee Estuary (2800 cfs) and Saint Lucie Estuary (950 cfs) ended
Monday, August 3rd. Since that time, releases at S-79 and S-80
have been limited to basin runoff.
Background
Locally moderate rains possible
along the east coast through Wednesday. A weak frontal boundary extends through the Lake Okeechobee
area. Look for some showers to focus near this boundary with the best
chance for rains near the coast of Martin/Saint Lucie counties. This
front will drift south to the Lower East Coast Wednesday before exiting on
Thursday. Some locally moderate rains are possible very near the coast
through Wednesday Residual light showers are
expected Thursday before dry, quite breezy, and slightly cooler conditions
prevail Friday through the weekend. The
next ten days precipitation outlook is near average with low confidence.
Kissimmee Watershed
In the Upper Kissimmee Basin over the past week the
Kissimmee Basin received less than 0.2 inch of rainfall. For the month so
far, rainfall was 12% and 0% of normal in the Upper and Lower Basins,
respectively. Total rainfall in the last 30 days was 1.0 inch in the
Upper Basin (34% of normal) and 0.6 inch in the Lower Basin (21% of normal)
(SFWMD Daily Rainfall Report 11/2/2009).
Lakes in the Kissimmee Chain of Lakes are within 1.0 foot below
their regulation schedules (USACE Kissimmee River Report 11/2/09 and/or SFWMD OASyS DualTrend or
LOGGERNET). Lakes Hart and Mary Jane are 0.9 foot below regulation
schedule. Lakes in the Alligator Chain are 0.9 foot below regulation
schedule. Lake Gentry is 0.2 foot below regulation schedule. East
Lake Tohopekaliga is 0.6 foot below regulation schedule. Lake
Tohopekaliga is 0.3 foot below regulation schedule; discharge at S61 is 0
cfs. Lakes Hatchineha and Cypress are 1.0 foot
below regulation schedule. Lake Kissimmee is approximately 0.9 foot below
regulation schedule. Discharge at Lake Kissimmee (S65) is 234 cfs.
In the Lower Kissimmee Basin (SFWMD OASyS
Dual Trend or LOGGERNET 11/3/2009) discharge at S65-A is 166 cfs.
Discharge at S65-C is 447 cfs with headwater stage at 35.8 foot.
Discharge at S65-D is 439 cfs. Discharge to Lake Okeechobee at S65-E is
43 cfs.
Water depths continue to recede on the floodplain in the Kissimmee
River Phase I restoration area, averaging 0.8 foot (SFWDAT 11/1/2009)*
River channel dissolved oxygen (DO) concentrations in the Phase I
area averaged 4.5 mg/L over the past week, well above the level of concern.
Okeechobee Field Station will be treating water lettuce and water
hyacinth this week in the lower Pool BC area of the Kissimmee River.
Two of the 21 horses that have been roaming the floodplain have
been captured and are under the care of Okeechobee County Animal Control.
Lake Okeechobee
According
to the USACE web site, Lake Okeechobee stage is 14.04 feet NGVD for the period
ending at midnight November 02, 2009, which is 0.10 foot lower than a week ago,
0.44 foot lower than a month ago, and 0.71 foot lower than a year ago.
The current stage is 0.99 foot below the historical average for this date and
0.08 foot above the simulated average using the current regulation schedule
(LORS2008). Total reported inflows are 57 cfs
and include flows through S65E (43 cfs)and Fisheating
Creek (14 cfs). According to Raindar there was negligible rain directly
over the Lake this past week. Lake outflows total 688 cfs, including S77
(297 cfs), S354 (145 cfs) and S351 (246 cfs). S308 and the L8 at Canal Point
are not reporting.
Current
total coverage of floating aquatic vegetation on the Lake is estimated at 4000
acres. One thousand acres of floating vegetation was treated in Fish
Eating Bay last week from Mayaca Cut to Observation
Island. Treatment of approximately 2000 additional acres is
planned. District crews flying the Lake last week reported seeing large
flocks of wading birds foraging in shallow areas in the Northwest marsh that
have been cleared as a result of the torpedo grass control program.
Florida Fish and Wildlife Conservation Commission
(FWC) reports seeing exceptional Chironomid blooms on
the Lake. Chironomids are an important food source for juvenile fish
and other aquatic organisms and are key indicators of improved lake
conditions. Their abundance has been limited over the past several
years. FWC is also reported good young of the year numbers for Largemouth
bass (a single transect in Fish Eating Bay yielded more fish than the entire
lake wide electro fishing study in 2008).
Saint Lucie Estuary*
Over
the past week, flow averaged 0 cfs at S-80 and 2 cfs at S308. Provisional
data indicates that discharge of 0.2 cfs occurred at S-97 on C-23 and 0 cfs at
S-49 on C-24. The current weekly average salinities (in bold) at the four
monitoring sites in the Saint Lucie Estuary are given below in practical
salinity units (psu), along with the previous week’s
(in parenthesis).
Weekly
Average Salinity (psu) |
|||
Sampling
Site |
Surface |
Bottom |
Envelope |
HR1
(N. Fork) |
18.9 (19.8) |
20.9
(21.1) |
|
Roosevelt
Bridge |
21.7 (21.4) |
22.4
(22.3) |
8.0
– 25.0 |
A1A
Bridge |
27.9 (28.4) |
29.8
(30.3) |
20.0
– 31.0 |
Average
salinity remained the same over the last week. Weekly average salinities
at Roosevelt Bridge and A1A Bridge are within the preferred range.
Salinity conditions in the estuary are good considering the time of year, the
location in the estuary, and salinity preference of the oyster, Crassostrea virginica.
Caloosahatchee Estuary*
During
the past week, flow averaged 0 cfs at S-79, 78 cfs at S-78, and 439 cfs at
S-77. The concentration of chlorides at the Olga Plant was 60 ppm on Monday, November 2nd. The current
weekly average salinities (in bold) at the six monitoring sites in the
Caloosahatchee Estuary are given below in practical salinity units (psu), along with the previous week’s (in parenthesis).
Weekly
Average Salinity (psu) |
||
Sampling
Site |
Surface |
Bottom |
Franklin
Locks (S-79) |
4.4
(1.6) |
5.5
(1.7) |
Rt.
31 Bridge |
5.3
(1.8) |
10.2
(4.0) |
I-75
Bridge |
5.6
(2.1) |
11.1 (6.2) |
Ft.
Myers Yacht Basin* |
11.5 (8.9) |
14.4 (14.3) |
Marker
52 |
11.9
(9.3) |
15.9
(16.1) |
Cape
Coral Bridge |
18.3
(15.7) |
19.5
(19.6) |
Shell
Point |
28.8
(26.6) |
29.4
(27.2) |
Sanibel |
31.9
(29.7) |
32.8 (31.0) |
*red
values are estimated using a regression relationship between salinity at Marker
52 and salinity at Fort Myers
Salinity
increased throughout the estuary last week. Salinity conditions in the
upper estuary are considered good. The estimated 30-day average salinity
at Fort Myers is 7.1 psu. Salinities at the
Cape Coral Bridge are within the preferred range for the oyster, Crassostrea virginica.
Salinity at Shell Point and the Sanibel Causeway indicate that conditions
are good for seagrass in the lower estuary and San
Carlos Bay. Therefore, conditions in the lower estuary and San Carlos Bay
are good.
Fish
and Wildlife Research Institute reports that Karenia
brevis, the Florida red tide organism, was not
detected in water samples collected this week alongshore of Pinellas, Manatee,
Charlotte, Collier and Monroe counties or offshore of the Florida Keys (Monroe
County). Three samples collected alongshore of Sarasota County (out of 28
total samples) ranged from background to very low concentrations of K. brevis. Samples collected alongshore and offshore
of Lee County ranged from not present to medium concentrations of K. brevis. An extensive fish kill in conjunction
with discolored water was reported approximately ten miles offshore, southwest
of Sanibel Island.
Monitoring
data collected by the River, Estuary and Coastal Observing Network of Sanibel-Captiva
Conservation Foundation indicated that chlorophyll ranged from 1.7 – 3.4 ug/l at Fort Myers and 1.0 – 4.1 ug/l
at Shell Point; DO ranged from 4.4 – 6.8 mg/l at Fort Myers and 4.2 – 6.4 mg/l
at Shell Point. Fort Myers values are from yesterday only, the recorder
has been down.
Biscayne Bay
Continuous
salinity measurements are now being measured at two sites in Biscayne
Bay*. Data will be reported on a monthly basis. This initial report
is not particularly detailed but will be refined in the future, as more data is
accumulated. Salinity at both sites was close to 20 ppt
at the end of September, and showed a general increase for most of the last
month (ranging from about 25 – 32 ppt).
Salinity at the southern station, BBCW10, is more variable than for
BBCW8. Recently, salinity has increased, most likely in response to
declining rainfall.
Average
Salinity (psu) |
|||
Sampling
Site |
August |
September |
October |
BBCW8 |
27.1 |
28.6 |
28.6 |
BBCW10 |
33.5 |
27.0 |
28.8 |
Water Conservation Areas (WCA)
This week’s pan evaporation of 1.22 inches* was similar to last
week’s, greatly exceeding rainfall in the conservation areas*. Stages
declined in all areas except for WCA-2B.
Stage Change:
WCA-1:
-0.08 foot
WCA-3A:
-0.15 foot
WCA-2A:
-0.17 foot
WCA-3B:
-0.08 foot
WCA-2B:
0.05
foot
NESRS:
-0.07 foot
Water depths are declining across the region from -0.06 foot to
-0.20 foot except in WCA-2B*. Gage 65 has now dropped below 2.5 feet, a
depth monitored for stress to trees on the tree islands in southern
WCA-3A. Marsh water stages in WCA-1 remain 0.5 foot below regulation in
zone B.* Stages in WCA-2A are 0.4 foot above regulation and are following
the gradual decreasing slope of the regulation schedule, which is preferred
going into the dry season for the wetlands. In WCA-3A, stages have
declined rapidly and are now 0.25 foot below regulation.
Water depths in the conservation areas show overall declines
relative to a month ago*. Greater Everglades’ depths are lower than they
were a week ago, a month ago, and a year ago.*
Everglades National Park
Like
the rest of the Greater Everglades, very little rain fell across Everglades
National Park (ENP) wetlands and Florida Bay. ENP stations measured 0 –
0.4 inch of rainfall. The basin-wide totals were 0.2 and 0.01 inch for
the ENP and C-111 basins, respectively.*
Stages*
declined across ENP wetland stations last week. Water levels in Shark
River Slough and at the Taylor Slough Bridge declined 0.2 and 0.5 inch,
respectively. To the south, water levels in the ENP panhandle and in
Craighead Basin declined 0.8 and 1.1 inches, respectively. Current water
levels at all ENP wetland stations are considered seasonally normal.
Salinity*
increased or remained steady across Florida Bay last week. In the
near-shore eastern Bay, salinity increased to the middle teens in Highway
Creek, to the low 20s in Long Sound, and to the middle 20s at the Little
Madeira Bay platform. Salinity remains in the low 30s further into the
Bay in Duck Key Basin. The 30 day moving average salinity at the Taylor
River platform (used for tracking the Florida Bay Minimum Flow and Levels)
increased slightly from 0.9 psu to 1.0 psu, with the daily mean salinity remaining steady near 1 psu. In the north central Bay, salinity increased
from the middle teens to the mid 20s in McCormick Creek, and after increasing
to the upper 20s, salinity settled back to the middle 20s in Terrapin
Bay. At the central Bay platform in Whipray
Basin, salinity was steady in the middle to upper 30s.
To
the west, in the upstream reaches of Shark River Slough, salinity remained <
1 psu. Current station salinities are
seasonally normal or slightly too moderately above normal across Florida Bay.
Water Supply
Groundwater
levels across the District are slowly declining. About half of both
Floridan and Surficial wells in the Kissimmee Basin
are at median water level values for this time of year, with the remainder
dropping into the lowest 30th to 10th percentile
range. Canal stages in the Upper East Coast (UEC) range from 18 to over
21 feet NGVD this week - well above the 14 foot agricultural pumping cutoff
level. Groundwater levels in the UEC are gradually declining while
remaining at expected values for this time of year in Saint Lucie County.
UEC groundwater conditions are generally lower to the south – in the 30th
percentile in Martin County and in the lowest 10th percentile far
northern Palm Beach County In the Lower East
Coast, groundwater levels in the United States Geological Survey (USGS) network
are at median values for most wells. There are several wells in
Miami-Dade County south of US 41 near Krome Avenue
that have dropped to below the lowest 10th percentile. Surficial aquifer wells in the Lower West Coast (LWC) are
at median levels and slowly dropping as the dry season progresses. Most
Lower Tamiami water levels in the USGS network in the
LWC are in the median range for this time of year, also declining
seasonally. Sandstone aquifer wells in the USGS network are declining and
are mostly in the lowest 10th to 30th percentile range,
with a few lower than 10 percent and one at median levels. Mid-Hawthorn
wells are mostly in the lower 10th to 30th percentile
range. Levels in the Mid-Hawthorn appear to be steady rather than declining at
present.
All
water supply risk indicators remain in the “low” risk category. The
projected LOK Stage for the next two months is in the Base Flow band. The
Palmer Index for LOK Tributary Conditions is classified as “near normal”, but
approaching “dry” The LOK Seasonal Net Inflow Forecast and the LOK
Multi-Seasonal Net Inflow Forecast are both projected as “very wet”, and the
CPC Precipitation Outlook is “above normal” for both one month and three
months. The Water Conservation Areas and the Lower East Coast service
areas 1, 2 and 3 remain in the “low” risk category.
LORS2008 (Lake Okeechobee Regulation Schedule)
Stages
in Lake Okeechobee are now in the Base Flow Band. Tributary inflows
continue to decrease and are nearing the “dry” category. The seasonal
outlook for net inflow into the Lake is for very wet conditions. The
multi-seasonal outlook is also very wet.
The
2008 LORS Release Guidance Flowchart calls for releases up to 450 cfs at S-79
and up to 200 cfs at S-80. Given current estuary conditions, the District
recommends discharge to the Caloosahatchee and Saint Lucie Estuaries continue
to be limited to basin run-off.
Because
conditions are nearing the “dry” band according to the 2008 LORS Release
Guidance Flowchart, no Lake Okeechobee releases to the WCAs are recommended.
* Go the FTP site for this week’s Ecological Conditions supporting documents
ftp://ftp.sfwmd.gov/pub/ecsdocs/2009_11_03.zip
CC:
George Horne