Weekly Estuarine
Conditions Update
As of October 5, 2009
St. Lucie
Estuary
Current Conditions:
Over the past week, flow averaged 89 cfs at S-80 and 0 cfs at
S308. Provisional data indicates that discharge of 121 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 St. 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 |
Palm
City Bridge (S. Fork) |
5.8 (2.7) |
7.9 (4.2) |
|
HR1
(N. Fork) |
8.9 (4.5) |
14.7
(8.1) |
|
Roosevelt
Bridge |
12.3 (8.4) |
15.5 (10.9)
|
8.0 – 25.0 |
A1A
Bridge |
18.1
(15.1) |
24.1
(23.4)
|
20.0
– 31.0 |
Average salinity increased over the last
week. Weekly average salinities at Roosevelt Bridge and A1A Bridge (bottom
salinity) are within the preferred range, surface salinity at A1A Bridge is
below the preferred range. Salinity conditions in the estuary are fair to
good considering the time of year, the location in the estuary, and salinity
preference of the oyster, Crassostrea virginica.
Caloosahatchee Estuary
Current Conditions:
During the past week, flow averaged 929 cfs at S-79, 434 cfs at S-78, and
0 cfs at S-77. The concentration of chlorides at the
Olga Plant was 51 ppm yesterday. 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) |
0.2
(0.2) |
0.2
(0.2) |
Rt.
31 Bridge |
0.2
(0.2) |
0.3
(0.2) |
I-75
Bridge |
0.3 (0.3) |
0.3
(0.5) |
Ft.
Myers Yacht Basin |
NR
(NR)
|
NR
(NR)
|
Marker
52 |
2.8 (2.3) |
5.4 (8.7) |
Cape
Coral Bridge |
7.9 (6.6) |
9.0 (11.4) |
Shell
Point |
21.6
(20.3)
|
22.7 (22.4) |
Conditions in the upper estuary west of Ft.
Myers remained similar to last week, with surface waters being fresh to Marker
52. In the lower estuary salinity, salinity decreased in bottom water and
increased in surface water, except at Shell Point where salinity increased at
both sensors. Salinity conditions in the upper estuary are considered good. Salinities at the Cape Coral Bridge are below
the preferred range for the oyster, Crassostrea virginica, and the range
preferred by seagrass, Halodule wrightii. Therefore, conditions in the lower
estuary are poor.
FWRI (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, Hillsborough, Manatee, Lee and Collier
counties or offshore of Sarasota County. Samples collected alongshore of
Sarasota County ranged from present to very low in five samples (out of 28
total samples). Two samples collected alongshore of Charlotte County also
contained background levels of K. brevis (research.myfwc.com/features/view_article.asp?id=9670).
Monitoring data collected by the River, Estuary and Coastal Observing
Network (RECON) of Sanibel-Captiva Conservation
Foundation (SCCF) indicated that chlorophyll ranged from 4.0 – 11.0 ug/l at Ft. Myers and 1.6 – 5.8 ug/l
at Shell Point; Dissolved Oxygen ranged from 1.8
– 7.7 mg/l at Ft. Myers and 3.0 – 6.7 mg/l at Shell Point (www.recon.sccf.org).
Biscayne Bay
Current Conditions:
Continuous salinity measurements are now
being measured at two sites in Biscayne Bay (see map in attached graphics
file). 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 showed a general decrease for most of
the last month with the southern station, BBCW10, being more variable then
BBCW8. Recently salinity has begun to
increase, most likely in response to declining rainfall.
|
Average
Salinity (psu) |
|
Sampling
Site |
August |
September |
BBCW8 |
27.3 |
28.5 |
BBCW10 |
33.6 |
26.8 |
click on “Current Week”
click on “Technical
Summary”
scroll to the bottom and
click on “Coastal Ecosystems”