Northern Tampa Bay LTPRG2008 MFL ReviewAugust 5, 2008

Minimum Flows and LevelsIn 1998 – the District adopted 41 cypress wetlands, 15 lakes, and 7 Floridan aquifer wells as minimum level sitesSince then, we’ve added 86 additional lakes (101 total – 69 in NTB area)Eight rivers (or river segments) adopted –including the Upper and Lower Hillsborough RiverTwo springs adopted (Crystal and Sulphur)The plan for further MFL adoption is revised and approved each year

Current MFL Sites in NTB areaLake

Wetland

Well

Current MFL Sites in NTB areaLake

Wetland

Well

Not MFL sites – for comparison purposes only

Assessment of MFLs

Long-term median for lakes and wetlandsLong-term average for seawater intrusion wellsLakes, wetlands and wells assessed for 6 and 10 -year periods for the ending years 1999-2007

Lake Carroll

30

31

32

33

34

35

36

37

38

39

4019

46

1948

1950

1952

1954

1956

1958

1960

1962

1964

1966

1968

1971

1973

1975

1977

1979

1981

1983

1985

1987

1989

1991

1993

1996

1998

2000

2002

2004

Wat

er L

evel

(Fee

t NG

VD) L

ake

Car

roll

Monthly DataPOR MedianSix-Year MedianTen-Year MedianTwenty-Year Median

Crooked Lake1977-1983

105

107

109

111

113

115

117

119

121

123

125

127

129

111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126

Predicted Lake Elevation (ft)

Mea

sure

d La

ke E

leva

tio(f

LOC

95% LPI

95% UPI

99% LPI

99% UPI

1983

1982

1980

1979

1978

1977

2008 MFL Assessment

Assessment through calendar year 2007Rule of thumb (not the final definition of compliance) –– > 0.5 feet above MFL value – meeting MFL– > 0.5 feet below MFL value – not meeting

MFL– In between – “close”

Wetlands – 2007 Results10-year

8 wetlands meeting minimum level 15 wetlands not meeting minimum level3 wetlands close to meeting minimum

level14 wetlands without enough data to determine1 wetland lost in 2007

Wetlands – 2007 Results6-year

14 wetlands meeting minimum level13 wetlands not meeting minimum level12 wetlands close to meeting minimum level1 wetland without enough data to

determine 1 wetland lost in 2007

Wetlands – 2007 Results2-year *

4 wetlands above minimum level elevation *31 wetlands below minimum level elevation * 4 wetlands close to meeting minimum

level * 1 wetland lost in 2007

* Two years is not enough data for a minimum level determination

4141Total

10N/A

412Close

3115Not Meeting MFL

414Meeting MFL

20072006

NTB Wetlands (2- year)

* Two years is not enough data for a minimum level determination

Variable Distribution of Withdrawals

2001

4141Total

1515N/A

32Close

1514Not Meeting MFL

810Meeting MFL

200720062002

NTB Wetlands (10- year)

41

18

4

13

6

2001

414141Total

151517N/A

323Close

151414Not Meeting MFL

8107Meeting MFL

200720062002

NTB Wetlands (10- year)

2001

4141Total

24N/A

1213Close

1310Not Meeting MFL

1414Meeting MFL

200720062002

NTB Wetlands (6- year)

41

17

5

15

4

2001

414141Total

2416N/A

12134Close

131018Not Meeting MFL

14143Meeting MFL

200720062002

NTB Wetlands (6- year)

Current MFL Sites in NTB areaLake

Wetland

Well

Section 21 MFL Wetland

40

42

44

46

48

50

52

54

56

1/1/2000 1/1/2001 1/2/2002 1/3/2003 1/4/2004 1/4/2005 1/5/2006 1/6/2007

Wat

er L

evel

(ft N

GVD

)

Low Rainfall Average RainfallHigh Rainfall

Lakes – 2007 Results10-year

11 lakes meeting minimum level 31 lakes not meeting minimum level 26 lakes close to meeting minimum level 1 lake without enough data to determine

Lakes – 2007 Results6-year

27 lakes meeting minimum level 15 lakes not meeting minimum level 26 lakes close to meeting minimum level 1 lake without enough data to determine

Lakes – 2007 Results2-year *

6 lakes above minimum level elevation * 43 lakes below minimum level elevation * 20 lakes close to meeting minimum level *

* Two years is not enough data for a minimum level determination

6969Total

00N/A

2026Close

439Not Meeting MFL

634Meeting MFL

20072006

NTB Lakes (2- year)

* Two years is not enough data for a minimum level determination

2001

6969Total

11N/A

2626Close

3131Not Meeting MFL

1111Meeting MFL

200720062002

NTB Lakes (10- year)

69

4

9

51

5

2001

696969Total

114N/A

26266Close

313152Not Meeting MFL

11115Meeting MFL

200720062002

NTB Lakes (10- year)

2001

6969Total

11N/A

2624Close

1516Not Meeting MFL

2728Meeting MFL

200720062002

NTB Lakes (6- year)

69

1

11

52

5

2001

696969Total

110N/A

26244Close

151659Not Meeting MFL

27286Meeting MFL

200720062002

NTB Lakes (6- year)

Meets MFL

Does not meet MFL

Very near MFL

Site lost

Not enough data

Lake MFL Status 2001 – 10 Year

Lake

Meets MFL

Does not meet MFL

Very near MFL

Site lost

Not enough data

Lake MFL Status 2007 – 10 Year

Lake

Meets MFL

Does not meet MFL

Very near MFL

Site lost

Not enough data

Lake MFL Status 2001 – 6 Year

Lake

Meets MFL

Does not meet MFL

Very near MFL

Site lost

Not enough data

Lake MFL Status 2007 – 6 Year

Lake

6969Total

115N/A

267Close

3142Not Meeting MFL

115Meeting MFL

20072000

NTB Lakes (10- year)

6969Total

17N/A

2615Close

1540Not Meeting MFL

277Meeting MFL

20072000

NTB Lakes (6- year)

MFL Wells – 2007 Results10-year

3 wells meeting minimum level4 wells close to meeting minimum level

MFL Wells – 2007 Results6-year

3 wells meeting minimum level4 wells close to meeting minimum level

MFL Wells – 2007 Results2-year *

* Two years is not enough data for a minimum level determination

3 wells meeting minimum level *1 well not meeting minimum level * 3 wells close to meeting minimum level *

MFL Status 2007 – 10 YearMeets MFL

Does not meet MFL

Very near MFL

Site lost

Not enough data

Lake

Wetland

Well

Meets MFL

Does not meet MFL

Very near MFL

Site lost

Not enough data

MFL Status 2007 – 6 Year

Lake

Wetland

Well

Meets MFL

Does not meet MFL

Very near MFL

Site lost

Not enough data

MFL Status 2007 – 2 Year

Lake

Wetland

Well

MFL Site EvaluationsSince 1998, staff has continued to evaluate, collect data, install additional instrumentation, and maintain instrumentation at all sitesWetlands are particularly complicated due to multiple instrumentation needs, maintenance, remoteness, etc.In many wetlands, issues include survey discrepancies, access issues, development effects, and reconsideration of site status.

2008 Assessment of Recovery Levels

Recovery Levels meant to serve as guidelines as to what the Floridan aquifer levels would be at 90 mgd, based on the District’s recovery assessment40 original wells – 2 since destroyedBased on long-term average

Recovery Wells – 2007 Results - 10-year

2 wells meeting recovery level31 wells not meeting recovery level5 wells close to meeting their recovery level2 wells lost

Recovery Status 2007 – 10 YearMeets REC

Does not meet REC

Very near REC

Well lost

Recovery Wells – 2007 Results - 6-year

8 wells meeting recovery level 21 wells not meeting recovery level9 wells close to meeting their recovery level

Recovery Status 2007 – 6 YearMeets REC

Does not meet REC

Very near REC

Not enough data

Recovery Wells – 2007 Results - 2-year *

1 well above recovery level elevation *33 wells below recovery level elevation *4 wells close to meeting their recovery level *

* Two years is not enough data to do a recovery level determination

Recovery Status 2007 – 2 YearMeets REC

Does not meet REC

Very near REC

Not enough data

General ConclusionsMFLs (and other data/observations) continue to show regional improvementCompliance of MFLs not achieved yet due to:– Cutbacks and distribution of withdrawals not

complete– Methodologies still in development– Limited time for assessment

Upcoming Recovery and MFL Issues

Evaluate the need for adjustments to MFL rules– Additions or replacement to sites– Additions or alterations to methodologies

Recovery Assessment AnalysesPeer Review