MEMORANDUM

TO: Water Management District Governing Board

FROM: Tom Mirti, Director, Division of Water and Land Resources

THRU: Hugh Thomas, Executive Director

DATE: June 11, 2018

RE: May 2018 Hydrologic Conditions Report for the SRWMD

RAINFALL

x District-wide rainfall in May averaged 7.59” across the District, about 50% above the long-term average May rainfall of 3.27”. All counties received well above average rainfall amounts, with Alachua and Baker counties receiving about 3 times normal amounts and Taylor County receiving almost 10” on average. Bradford County received the least amount of rain on a county-wide basis, about 5” total. Highest rainfall totals occurred in San Pedro Bay in Madison and Taylor Counties—above 12” in some locations, while the upper New River basin and northern Lafayette County received under 4” (Table 1, Figures 1 and 2). x The highest gaged monthly rainfall total of 10.74” was recorded at the Sneads Smokehouse Lake rainfall station in northern Jefferson County, and the highest daily total of 4.90” was recorded on May 16 at the Alligator Lake rainfall gaging station in Columbia County. The lowest gaged monthly total was 4.60” at the Sanderson rainfall station in southern Baker County. x The rainfall average by county across the District for the 12-month period ending May 31 was 58.2”, compared to the long-term average of 54.6". The District has transitioned to a modest surplus of almost 4” over the past month. All major river basins improved during May; the basin is carrying a 9” annual surplus, with limited areas in northern Alachua County showing a 20” surplus. The Waccasassa River basin improved to a surplus status of 2”, and the basin continued to improve, although there is still a 10” deficit in central Madison County (Figure 3). x Average District 3-month rainfall ending May 30 totaled 15.9”, about 40% above the long-term average for the period of 11.3”. The Aucilla, Coastal, and Waccasassa basins experienced a 7” net positive shift due to the May rains and only the New River portion of the Santa Fe basin is experiencing a deficit over the past three months (Figure 4).

SURFACEWATER

x Rivers: Virtually all long-term monitoring stations ended May much higher than they began, and 10 of 14 District stations were in the above normal (between the 75th and 90th percentile) or high (above the 90th percentile) categories. The set provisionally new daily records for May, as did the Little River near Adel, GA. All Coastal Basin Rivers rose into the high category, along with the Withlacoochee River in Georgia, the Upper Suwannee in both and Georgia, and Upper Santa Fe rivers. Only the Lower Suwannee River remains in the normal category (between the 25th and the 75th percentiles), generally since runoff from the upper portions of the basin had not yet reached the lower reaches of the river. Flow statistics for major river stations are presented graphically in Figure 5, and river level conditions relative to historic conditions are provided in Figure 6. x Lakes: District lakes again rose by an average of 2” during May. Lake Sampson in Bradford County declined 0.2’, while Alligator Lake in Columbia County rose sharply by 0.8’ after the heavy rainfall event at mid-month. Figure 7 shows District monitored lake levels along with long-term minimum, average and maximum levels. WLR 1 x Springs: Flows at 19 springs in the District were measured by the USGS, District staff, and District contractors during May. Many springs flowing directly into the Suwannee River above Branford began to backflow in response to rising river levels, including at Lafayette Blue Spring. Two Outstanding Florida Spring Groups, the and the , experienced rebounds in flows due to the heavy rains and rising groundwater levels. Data from these springs is provided on Figures 8 and 9, respectively.

GROUNDWATER

On a District-wide basis, Floridan aquifer water levels rose by 0.3’ during May, ending the month at the 65th percentile on average. High aquifer levels (above the 75th percentile) in the and Santa Fe River basins expanded again slightly relative to the previous month. Most of the remainder of the District lies within the normal range of levels (between the 25th and 75th percentiles). Low groundwater levels (below the 25th percentile) expanded in Madison County and extended into northern Lafayette County, representing about 10% of the District area (Figure 10). A representative set of hydrographs of long-term Floridan aquifer wells are provided in Figure 11 along with summary statistics, and regional long-term well conditions are shown on Figure 12 along with a description of Floridan aquifer characteristics.

HYDROLOGICAL/METEOROLOGICAL INFORMATION

x The 2017-2018 La Niña episode ended officially in early May, according to the National Weather Service’s Climate Prediction Center (CPC). The CPC has modified earlier projections of an extended neutral El Niño Southern Oscillation phase and is now projecting a transition to El Niño conditions by late 2018. x The U.S. Drought Monitor report for the week ending June 7 showed no drought conditions anywhere in the District, nor anywhere else in Florida. Peninsular Florida displayed unusually moist conditions according to the Palmer Drought Severity Index.

CONSERVATION

Water conservation is necessary to sustain healthy groundwater levels and flows in District springs and rivers. All users are urged to eliminate unnecessary uses. Landscape irrigation during Daylight Savings Time (after March 10, 2018) is limited to twice per week based on a District water conservation rule that applies to residential landscaping, public or commercial recreation areas, and businesses that are not regulated by a District-issued water use permit. Information about SRWMD’s year-round conservation measures is available at www.mysuwanneeriver.com.

This report is compiled in compliance with Chapter 40B-21.211, Florida Administrative Code, using rainfall (gage-adjusted radar-derived estimates), groundwater (97 wells), surfacewater (35 stations), and general information such as drought indices and forecasts. Data are provisional and are updated as revised data become available. Data are available at www.mysuwanneeriver.com or upon request.

ACKNOWLEDGEMENTS The Hydrologic Conditions Report is a monthly effort of the Water and Land Resources Division’s Data Collection Program. Acknowledgement is made to the following staff for their significant contributions, hard work and dedication to the timely production of this report: Data Collection: Kevin Jones, Henry Richardson, and Vince Robinson QA/QC and Reporting: Fay Baird, Ross Davis, Mark Hinz Administrative Support/Document Preparation: Pennie Flickinger

2

WLR 2 Table 1: Estimated Rainfall Totals by County (inches)

County May May Month % Total Last Annual % 2018 Average of Normal 12 Months of Normal Alachua 6.66 2.27 294% 49.36 97% Baker 6.28 1.89 333% 42.84 86% Bradford 4.98 2.22 224% 48.16 93% Columbia 7.92 3.21 247% 48.65 95% Dixie 8.23 3.43 240% 54.51 92% Gilchrist 7.78 3.36 232% 50.33 88% Hamilton 8.04 3.16 254% 44.24 85% Jefferson 8.95 5.88 152% 46.04 76% Lafayette 5.80 3.33 174% 61.39 109% Levy 6.88 2.67 258% 47.90 80% Madison 8.57 4.73 181% 44.86 80% Suwannee 6.39 3.24 197% 55.54 105% Taylor 9.50 4.16 229% 53.65 90% Union 5.59 2.21 253% 45.88 85%

May 2018 District Average: 7.59 May Long-Term Average (1932-2017): 3.47 Historical 12-month Average (1932-2017): 54.61 Past 12-Month Total: 58.18 12-Month Rainfall Surplus/Deficit: 3.57

Figure 1: Comparison of District-wide Monthly Rainfall (Rainfall reported in inches) 20

18

16

14

12

10

8 Rainfall (inches) Rainfall 6

4

2

0 Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun

Past 13 Months Average Maximum Minimum

WLR 3 Figure 2: May 2018 SRWMD Gage-adjusted Radar Rainfall Estimate

WLR 4 Figure 3: 12-Month Rainfall Surplus/Deficit by River Basin through May 31, 2018

Figure 4: 3-Month Rainfall Surplus/Deficit by River Basin through May 31, 2018

WLR 5 Figure 5: Daily River Flow Statistics June 1, 2017 through May 31, 2018 75 - 100 25 - 75 10 - 25 Percentile 0 - 10 Past 12 Months Flow Suwannee River at Fargo, GA 10,000

10000

1,000

1000

100

100 10

10 1

Suwannee River at White Springs 0 1 Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun

100000 100000 Suwannee River at Branford

10000

10000

1000

Suwannee River at Ellaville 100 1000 Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun

100000 RIVER FLOW, CUBIC FEET PER SECOND PER FEET CUBIC FLOW, RIVER Withlacoochee River near Pinetta near Statenville, GA 50000

10000

5000

1000

500 100

50 10 Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun

WLR 6 Figure 5, cont: Daily River Flow Statistics June 1, 2017 through May 31, 2018 75 - 100 25 - 75 10 - 25 Percentile 0 - 10 Past 12 Months Flow 30000 Santa Fe River at Worthington Springs Santa Fe River near Fort White above SR47 Bridge 10,000

1,000

100 3000

10

1

0 300 Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun

700 16000 Ichetucknee River at US 27 Steinhatchee River above US19

600

1600

500

400 160

300

16

200

100 1.6 Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun

RIVER FLOW, CUBIC FEET PER SECOND PER FEET CUBIC FLOW, RIVER Econfina River on Salt Road above US 98 10,000 Aucilla River at Lamont 1,000

1,000

100

100

10

10

1 1

0 0 Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun

WLR 7 WLR 8 Figure 7: May 2018 Lake Levels

SRWMD lakes react differently to climatic changes depending on their location in the landscape. Some lakes, in particular ones in the eastern part of the District, are embedded in a surficial or intermediate aquifer over relatively impermeable clay deposits. These lakes rise and fall according to local rainfall and surface runoff. They retain water during severe droughts since most losses occur from evaporation. Other lakes, such as Governor Hill and Waters Lake, have porous or “leaky” bottoms that interact with the Floridan aquifer. These lakes depend on groundwater levels to stay high. If aquifer levels are low, these lakes go dry even if rainfall is normal.

The District currently monitors 14 lakes on a long-term basis; much of the data was originally provided by volunteer observers. Monitoring records began in the 1970s, except for Lakes Butler, Sampson, and Santa Fe, which started in 1957.

Feet Above or Below Historic Average

WLR 9

Figure 8: Discharge Over Past 12 Months, Wacissa River near Wacissa (discharge in cubic feet per second)

WLR 10 Figure 9: Discharge Over Past 12 Months, Ichetucknee River near Hildreth (discharge in cubic feet per second)

WLR 11 WLR 12 Figure 11: Monthly Groundwater Level Statistics Maximum 1976-2016 Levels June 1, 2017 through May 31, 2018 Period of Record Beginning 1976 Average Since 1976 Minimum 1976-2016

Past 12 Months

Madison County N010719001 Suwannee County S021335001 near Greenville near Live Oak 86 56

52 81 48

76 44

40 71 36

66 32 Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May

Columbia County S041705001 Hamilton County N011422007 Lake City near Jasper 56 68

64

52 60

56

48 52

48

44 44

40

40 36 Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May

Lafayette County S061114001 Taylor County S040736005 near Mayo Perry 73

40 UpperFloridan AquiferElevation above NGVD 1929, Feet 69

37

65 34

61 31

57 28 Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May

WLR 13 Figure 11, cont.: Groundwater Level Statistics Maximum 1976-2016 Levels June 1, 2017 through May 31, 2018 Period of Record Beginning 1976 Average Since 1976 Minimum 1976-2016

Past 12 Months

Union County S051933001 Alachua County S081703001 near Lake Butler at High Springs 63.0 43.0

60.5 39.5 58.0

55.5 36.0

53.0 32.5 50.5

48.0 29.0 Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May

Gilchrist County S091607001 Bradford County S072132001 near Trenton near Graham 78 70.0 74 67.5 70

66 65.0 62

58 62.5 54 60.0 50

46 57.5 42

38 55.0 Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May

Dixie County S101210001 Levy County S131736001 at Cross City near Bronson 40 55 Upper Floridan Aquifer Elevation above NGVD 1929, Feet 1929, NGVD above Elevation Aquifer Floridan Upper

37 50

34 45

31 40

28 35 Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May WLR 14 WLR 15 Figure 12b: Regional Long Term Upper Floridan Aquifer Levels

Data through May 2018

57 Newberry Well Alachua County 1958 Taylor 53

Sanderson 49 Lake City DOT

Raiford 45

41 Newberry

37

33

Taylor and Sanderson wells courtesy of SJRWMD

66 64 USGS Taylor Well USGS Sanderson Well 64 Baker County 62 Baker County 62 1963 1963 60 60 58 58 56 56 54 54 52 50 52 48 50 46 48 44 46 42 40 44

70 64 DOT Lake City Well USGS Raiford Well

Upper Floridan AquiferElevation above NGVD 1929, Feet Columbia County 68 Bradford County 62 1948 1959 60 66 58 64 56 54 62 52 60 50 58 48 46 56 44 54 42 52 40 38 50

WLR 16