Alafia River/Tampa Bypass Canal
Hydrobiological Monitoring Program
Overview of Monitoring Results
& Effects of Tampa Bay Water
Withdrawals
August 10, 2006
Robert McConnell, M.S. - Tampa Bay Water
Robert Woithe, Ph.D. - PBS&J
Presented at the Agency on Bay Management’s Natural
Resources / Environmental Impact Review Committee Meeting
Hydrobiologic Monitoring Program
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Permit-required monitoring
– Hillsborough River / Tampa
Bypass Canal WUP
– Alafia River WUP
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HBMP monitoring requirements
– Hydrology
– Water quality
– Biota
– Habitat/vegetation
– Critical indicators and criteria
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Incorporates data from other
Agency monitoring programs
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HBMP Annual Meetings
− Review data
− Discuss analysis / interpretation
− Evaluate monitoring program
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Cost: approx. $1 million per year
Enhanced Surface Water System
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Enhanced Surface Water System
(ESWS)
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ESWS annual average ~60 mgd
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Manage and optimize withdrawal, conveyance,
and storage
TBC/Hillsborough River, Alafia River
Surface water treatment plant
Tampa Bay Regional Reservoir
TBC/Hills. River system - 75%
Alafia River system - 25%
Reservoir used during dry periods
Permitted withdrawal schedules
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Increase rate with increasing flows up to a
maximum; no withdrawals below a designated
low flow
Preserves high and low flows in river systems;
maintains natural range of variability
TBC/Alafia HBMP Design
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Primary Objectives
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Characterize indicators within
river segments (strata)
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Evaluate flow/parameter
relationships
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Key indicator is change in
salinity zones
Sampling extensive in four
reporting units
Hillsborough River
– TBC/Palm River
– McKay Bay
– Alafia River
Other Agency data used for
Hillsborough Bay
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TBC/Alafia HBMP Data Collection
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Monitoring Elements
– Hydrology/Water Quality*
– Benthic Invertebrates*
– Zooplankton and Larval Fishes - USF College
of Marine Science
– Adult and Juvenile Fishes - Florida Fish and
Wildlife Research Institute
– Water Dependent Birds*
– Seagrass - SWFWMD and City of Tampa
– Wetland Vegetation*
*Monitoring performed by PBS&J
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Types of Data
– Continuous (salinity every 15-minutes)
– Monthly (water quality, fish, plankton, benthos)
– Bimonthly (bird surveys)
– Annual (vegetation surveys)
– Additional data from EPCHC, FWRI, USF,
SWFWMD, USGS
HBMP-Related Milestones
WUPs Issued
HBMP Design Workshops
1999
HBMP Sampling Begins
April 2000
HBMP Annual Reports Begin
July 2001
TBC Pump Station - Online
Sept 2002
Alafia River Pump Station Online
Feb 2003
HBMP Year-3 Report:
(Pre-Operational)
Aug 2003
Tampa Bay Regional Reservoir
Construction Completed
Feb 2005
Tampa Bay Regional Reservoir
Online to Regional System
Jan 2006
HBMP Year-6 Report
(initial Post-Operational)
July 2006
C.W. Bill Young Regional Reservoir
C.W. Bill Young Regional Reservoir
Year 6 Interpretive Report
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Evaluated HBMP data under pre- and post-operational
conditions (April 2000 through September 2005)
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Included data from other monitoring programs from 1975 to
September 2005
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Objective: answer specific characterization & assessment
questions for each reporting unit
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Focused on:
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Flows & Withdrawals
Salinity (hydrodynamic & regression models)
DO & Chlorophyll-a (regression models)
Key Biotic Indicators (statistical models)
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Discussed at May 2006 HBMP Annual Meeting
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Report submitted to SWFWMD July 2006
Year 6 Interpretive Report
Characterization & Assessment
1. Daily flows in the Period of Study and Historic Record
2. Withdrawals and their effect on Daily Flows
(“observed” vs. “reconstructed”)
3. Intra- and inter-annual variations in Salinity
4. Salinity variations attributable to Withdrawals
(“observed” vs. “reconstructed”)
5. DO & Chlorophyll a intra- and inter-annual variations
6. DO & Chlorophyll a variations attributable to Withdrawals
(observed vs. reconstructed)
7. Key Biotic Indicators intra- and inter-annual variation
8. Key Biotic Indicator variation attributable to Withdrawals
The Five HBMP Reporting Units
Hillsborough River
boundary at Dam
(north of figure area)
Alafia River
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Operational salinities within baseline levels
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Difference between Observed vs. Reconstructed flows far less
than between wet vs. dry year flows
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Largest 90th percentile salinity differences in bottom layer and
between Rkm 5 and Rkm 9 (with and without withdrawals)
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Small differences in isohaline locations
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No low DO or high chlorophyll-a attributable to withdrawals
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No fish, plankton, or benthic
macroinvertebrate changes
attributable to withdrawals
(with and without withdrawals)
Alafia River Flows – 1975 to 2005
dry vs. wet year difference
much greater than
measured vs. reconstructed
Alafia River Flows & Withdrawals
Alafia River Baseline Salinity
AR1
AR4
AR3
AR6
Alafia River Bottom Layer
Median Salinity Changes
Alafia River 90th Percentile Salinity Changes
Alafia Vegetation by River Kilometer
Bottom Layer
Salinity Changes
Juncus Marshes
Alafia 0.5 & 18 psu Isohalines
Small differences in isohaline location
Alafia 0.5 & 18 psu Isohalines
Small differences in
isohaline locations
Alafia 0.5 & 18 psu Isohalines
Less than 120 m median
difference in isohaline
location
Less than 60 m median
difference in isohaline
location
Biological Components
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Identified several fish, plankton,
& benthic macroinvertebrate
indicators
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Principal Components Analysis
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Salinity preference and tolerance
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Flow relationships
Indicators
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Analyzed: Abundance, Distribution, Species Richness, Diversity
for many indicator species
Fish
Benthic Macroinvertebrates
Blue crab
Mosquito fish
Pink shrimp
Grass shrimp
Bay anchovy
Sheepshead
Silver perch
Menhaden
Snook
Sand seatrout
Spotted seatrout
Striped mojarra
Tidewater mojarra
small mojarra
Seminole killifish
Other Gobys
Pinfish
Spot
Rainwater killifish
Silversides
Southern kingfish
Clown goby
Striped mullet
White mullet
Thread herring
Sailfin molly
Red drum
Hogchoker
Oligohaline-Stenohaline
•Chironomus spp. - Insect
•Corbicula fluminea – Asian clam
•Polymesoda carolinae – Carolina marsh clam
•Polypedilum halterale - Insect
•Polypedilum scalaenum - Insect
•Tagelus plebeius – Stout razor clam
•Grandidierella bonnieroides – Amphipod
Oligohaline-Mesohaline –“moderately”
euryhaline
•Cyathura polita - Isopod
•Edotea triloba - Isopod
•Laeonereis culveri – Culver’s sandworm
•Mytilopsis leucophaeata – Dark false mussel
Indicators
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Large interannual variability in abundances, river locations,
salinity at capture (many species)
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Large interannual variability in flow and salinity
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Somewhat correlated to flow (this and previous studies)
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Flow or salinity change required for indicator response
much greater than flow or salinity changes observed or
predicted for the Tampa Bay Water withdrawals
Hillsborough River
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Operational salinities within baseline levels
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Difference between Observed vs. Reconstructed flows far less than
between wet vs. dry year flows
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2000 to 2002 Period exceptionally low flow
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Little to no difference in median salinities
(with and without diversions)
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Very small difference in 90th percentile
(highest) salinities (with and without diversions)
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Largest 90th percentile salinity differences
in Rkm 3 bottom layer
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No high chlorophyll-a attributable to diversions
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< 0.5% increase in low DO attributable to diversions
Hillsborough River Flows – 1988 to 2005
dry vs. wet year difference
much greater than
measured vs. reconstructed
Hillsborough River Baseline Salinity
HR1
HR3
HR6
Hillsborough River
Bottom Layer
Median Salinity
Changes
(due to withdrawals)
Identical to pattern for
surface & middle layers
(median)
Hillsborough River 90th Percentile Salinity
Changes (due to withdrawals)
Hillsborough Ave
Columbus Dr
Hillsborough River Salinity
Little difference
between with and
without withdrawal
scenarios
Hillsborough River Salinity Differences
Stratum HR3 Surface Layer
90 percentile difference <1 psu
50th percentile difference <0.2 psu
th
Stratum HR3 Bottom Layer
90 percentile difference <2 psu
50th percentile difference <0.2 psu
th
TBC/McKay Bay
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Operational salinities within baseline levels
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Small differences in median salinities (with and without
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1.5 to 2 psu differences in 90th percentile salinities
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Salinity differences greatest in surface layer
withdrawals)
(contrasts with Alafia & Hillsborough)
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Models suggest:
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Increasing flow decreases DO
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Increasing flow increases
Chlorophyll a in McKay Bay
TBC Flows 1983 to 2005
TBC/McKay Bay Baseline Salinity
TBC - PR3
McKay
TBC Median
Salinity
Changes
Greatest Changes in
Surface Layer
TBC 90th
Percentile
Salinity
Changes
Greatest Changes in
Surface Layer
Hillsborough Bay
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Bay salinities during production were generally lower than
baseline salinities
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Flows into Bay during production were generally at the high end
of normal
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Scenarios were run using the maximum possible permitted
withdrawals, maximum production by the Desalination Plant,
and 1998 to 2002 flows (when flows were very low)
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99% of Alafia area differences <0.6 psu
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99% of Hillsborough area differences <1 psu
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99% of TBC area differences <0.5 psu
2002 to 2006 Hillsborough Bay Flows &
Withdrawals
Hillsborough Bay Flows 1988 to 2005
Hillsborough Bay Pre-operational &
Operational Salinities
Hillsborough Bay Baseline vs. Operational
Salinities
Summary
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Results consistent with predictions and assumptions for WUP
studies
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Operational salinities within baseline levels for all reporting units
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Operational period had above average flows
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Difference between Observed vs. Reconstructed flows less than
between wet vs. dry year flows
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Small differences in isohaline locations (due to withdrawals)
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Largest salinity differences in bottom layer of Alafia and
Hillsborough and surface layer of TBC/McKay Bay
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Few or no low DO or high Chlorophyll-a values attributable to
withdrawals
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No fish, plankton, or benthic macroinvertebrate changes
attributable to withdrawals
Status and Next Steps
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No changes in HBMP sampling currently proposed
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Evolving Program - fish sampling in Hillsborough Bay near
mouth of Alafia River added Water Year 2005
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Will continue Annual Data Reports (next report in July 2007)
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Results to-date provide opportunity to optimize locations of
continuous salinity recorders (for HBMP and other programs)
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Initiated working group to evaluate tools and potential targets for
tracking changes and acceptable impacts
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Next Interpretive Report anticipated July 2009 (Year 9)
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Additional information and documents: Tampa Bay Water
website (www.tampabaywater.org) or Records Department