Produce the most accurate discharge estimate possible by measuring a series point velocities within a selected submerged passage cross- section. METHO

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1 MAKING DISCHARGE MEASUREMENTS WITHIN SUBMERGED CONDUITS PRESENTED BY: PETE BUTT KARST ENVIRONMENTALSERVICES, INC.

2 Produce the most accurate discharge estimate possible by measuring a series point velocities within a selected submerged passage cross- section. METHOD GOAL

3 APPLICATIONS Measure discharge of a spring vent lying beneath a surface water body. Determine proportion of flow contribution of multiple/tributary conduits within a cave system. Measure discharge/velocities at a discreet passage locations in support of other studies (dye trace, biological studies, etc.)

4 METHOD SYNOPSIS 1) Select suitable passage cross-section. section. 2) Fit support poles into cross-section. section. 3) Record relative positions of poles, walls and measurement stations. 4) Make and record as many point velocity measurements as practical (near-wall points are critical). 5) Plot support pole, wall and station data (X & Y points). 6) Use contouring program to process spatial and velocity data (X,Y & Z points).

5 ENVIRONMENTAL Depth Visibility Sediments Bottom Time Flow Passage Configuration/Shape PERSONAL Patience Temp. Tolerance CHALLENGES TECHNICAL Instrumentation Instrument Support Design and Set-up U/W Communication Experience/Training Number of Stations Level of Detail: Stations and Walls Data Processing

6 Standard Flowmeter Configuration

7 Equipment Development

8 FLOWMETER Marsh-McBirney McBirney Model 2000 Flowmeter Underwater Housing w/ controls Weights Data Slate SETTINGS Fixed Point Averaging used. 60 second periods used.

9 Underwater Flowmeter Controls Detail

10 Support Poles and Set-up Gear Telescoping Poles w/marks Post level, plumb bob Pocket Rod Tape Spring clips Set-up/drafting slate

11 Probe Clamp and Pole

12 Grid Setup: 1) Install and Level Horizontal Poles

13 Grid Setup: 2) Install and Square-up up Vertical Poles

14 Grid Setup: 3) Measure Wall and Pole Positions, Begin Flow Measurement

15 Croaker Hole

16 Grid Set-up I

17 Grid Set-up II

18 Finished Cross-section section Grid Set-up

19 Flowmeter/Housing in Operation

20 Underwater Data Recording

21 UNDERWATER TASK COMPLETION TIMES New support set-up: minutes Subsequent visit it set-ups: minutes Take velocities at stations: minutes Optimal maximum operating depth based on above: feet

22 Method Development

23 Field Data Layout and Input

24 CROAKER HOLE SPRING X,Y & Z Data Spreadsheet for Surfer 8 Table 3. Croaker Hole XYZ Grid Data December 11, FROM HAND PLOT: X Y Z (Velocity) Station # X Plot Y Plot

25 CROAKER HOLE SPRING Station Positions (X,Y) for Surfer 8

26 CROAKER HOLE SPRING Stations & Surfer Velocity Contours (X,Y & Z)

27 CROAKER HOLE SPRING Final Surfer Contour & Q (December 11, 2002 Measurement: CFS)

28 CROAKER HOLE SPRING Surfer 8 Grid Volume Computations TABLE 2. CROAKER HOLE SPRING, DECEMBER 11, SURFER 8 GRID VOLUME COMPUTATIONS AND GRIDDING REPORT UPPER SURFACE Grid File Name: C:\PROJECTS\KARST ENVIRONMENTAL\Croaker Hole\Dec 02\Croaker Hole SURFER XYZ T3 BLF.grd Grid Size: 171 rows x 261 columns X Minimum: 0 X Maximum: 13 X Spacing: 0.05 Y Minimum: 0 Y Maximum: 8.5 Y Spacing: 0.05 Z Minimum: Z Maximum: LOWER SURFACE Level Surface defined by Z = 0 VOLUMES Z Scale Factor: 1 Total Volumes by: Trapezoidal Rule: Simpson's Rule: Simpson's 3/8 Rule: CUT & FILL VOLUMES Positive Volume [Cut]: <<<<<<Flow Rate in CFS Negative Volume [Fill]: Net Volume [Cut-Fill]: AREAS Planar Areas Positive Planar Area [Cut]: <<<<Cross-section section area in Square Feet. Negative Planar Area [Fill]: Blanked Planar Area: 0 Total Planar Area: Surface Areas Positive Surface Area [Cut]: Negative Surface Area [Fill]:

29 UNDERWATER DISCHARGE MEASUREMENT Location: CROAKER HOLE SPRING Date: December 11, 2002 Putnam County, Florida Time Start: 14:22 Personnel: Method: Peter Butt, Tom Morris, Mark Long Grid within irregular conduit Time End: 15:55 Instrument: MMB2000 FLO-MATE in U/W case, probe on support poles Analysis Method: Surfer 8 with kriging Island Spring Total Discharge: CFS MGD GPM Total Cross-sectional Area: square feet Avg. Station Point Velocity: feet/second Cross-section Depth: feet deep Msmt. Periods: 60 seconds Velocity Reading by Station: Station # Point Velocity Station # Point Velocity (All velocity readings in feet per second.)

30 IMPROVING ACCURACY Increase number of stations. Take velocity readings closer to walls, especially in high velocity areas. Investigators should stay out of conduit s flow path as much as possible. After initial visit, replicate support grid with improvements and more measurements.

31 LAKE APOPKA GOURDNECK SPRING Lake County, Florida

32 LAKE APOPKA GOURDNECK SPRING Lake County, Florida

33 ISLAND SPRING Wekiva River, Seminole County

34 ISLAND SPRING Wekiva River, Seminole County

35 WEKIVA FALLS RESORT Lake County, Florida

36 WEKIVA FALLS RESORT Lake County, Florida

37 Horizontal Wire Grid Support

38 WEKIVA FALLS RESORT Lake County, Florida

39 WELAKA SPRING, Putman County, Florida North and South Vents

40 BLUE SPRINGS STATE PARK Volusia County, Florida

41 Movable Horizontal Support Pole

42 BLUE SPRINGS STATE PARK Volusia County, Florida

43 BLUE SPRINGS STATE PARK Volusia County, Florida

44 Acknowledgements St. John s River Water Management District: John Richmond Larry Fayard Dan Singletary Bruce Lafrenz Mark and Annette Long Bill Wilson, Subsurface Evaluations, Inc.

45 KARST ENVIRONMENTAL SERVICES, INC NE COUNTY ROAD 340 HIGH SPRINGS, FLORIDA (386)