Information Briefing Regarding CO-OPS’ Microwave Water Level (MWWL ) Activities

1. MWWL Activities Briefing Information Briefing Regarding CO-OPS’ Microwave Water Level (MWWL) Activities Manoj Samant October 24, 2012

2. Agenda • CO-OPS MWWL Activities • History • Testing and Analysis • Guidance • - Status • - Summary

3. CO-OPS MWWL Activities - History • Testing is done for four MWWL sensors at NSWC Carderock, MD • Miros Sm-094, Design Analysis WaterLog® H-3611i, Ohmart/VEGA VEGAPULS 62, and Sutron RLR-0002 • Additional field testing and comparison with NWLON data for 3 to 5 years done at Duck, NC; Money Point, VA; and Fort Gratiot, MI; • MWWL-Aquatrak® sensor data was in agreement • Additional testing done on four sensors at Duck Pier for 3 years • Impact of large surface gravity waves - with significant wave heights (amplitudes) of 1 meter and larger, and periods of 10 seconds and longer, and strong long shore and cross shore currents noted. • Observed large microwave-Aquatrak® differences with high energy events. • Design Analysis WaterLog ® H-3611i sensor selected based upon high reliability, low maintenance, and cost.

4. CO-OPS MWWL Activities – Testing, Analysis, and Guidance • General guidance translated into specific guidance and related to NWLON primary sensor standard deviations- 5 year average of monthly standard deviations threshold selected (2 cm SD value). • Requirements for MWWL Sensor Installation • Stable vertical infrastructure, • No sea surface ice, • Protected areas (semi-enclosed, fetch limited coastal regions with a small wave environment)

5. Sample NWLON Standard Deviation, Air and Water Temp

6. Monthly Average Standard Deviation of Aquatrak Sensor and Surface Wave Indication

7. Sample Graph Showing 5-Year Average of Monthly Standard Deviations of NE NWLON Stations

8. CO-OPS MWWL Activities – Limited Acceptance Report • Limited Acceptance of the Design Analysis WaterLog H-3611i Microwave radar Water Level Sensor Test and Evaluation Report published by CO-OPS in December 2010, which is available at http://tidesandcurrents.noaa.gov/publications/Technical_Report_NOS_CO-OPS_061.pdf • Report includes detailed comparison of MWWL vs NWLON reference sensors at Port Townsend, WA; Money Point, VA, Fort Gratiot, MI, and Bay Waveland, MS. • Testing and analysis supports operational use of the WaterLog® Microwave radar sensor in semi-enclosed, fetch limited coastal regions with a small wave environment. • Report also includes description of a 5 step lab verification test procedure that is required prior to field deployment.

9. CO-OPS MWWL Activities – Transition to Operations • CO-OPS formed a MWWL Transition to Operations (MWWL TOP) committee at the end of FY 11. Currently there are 10 members and meetings are held monthly. • MWWL TOP Committee - Oversight of all of transition activities – planning, testing, documentation, SOP, budget, schedule, operations, and implementation plan. These are multi year efforts. • MWWL TOP Committee will make a recommendation of which sites are suitable for MWWL transition. • Advantages of transitioning to MWWL sensor - no-diving, reduced AI time, no-corrosion, removal of dissimilar metal effects, no reduction in accuracy under limited acceptance criteria.

10. CO-OPS MWWL Activities – Implementation Guidelines • “Implementation of MWWL sensors into NWLON Operations – Requirements for simultaneous comparisons between sensors”, S K Gill, 1/14/2011 published. • “Implementation of MWWL sensors into NOAA Hydrographic Survey Operations - Requirements for simultaneous comparisons between sensors”, S K Gill 1/14/2011 published. • These two documents provide the roadmap for how simultaneous comparison will be done for control and subordinate stations. • Guidelines for Implementation of Microwave Water Level Sensors for Short Term Water Level Station Deployments is being drafted and reviewed.

11. CO-OPS MWWL Activities – Recent Projects • Currently MWWL sensor installed at 11 stations – Duck, NC; Port Townsend, WA; Fort Gratiot, MI: Bay Waveland, MS; East Fowl River, AL, West Fowl River, AL; Dog River, AL, Bayou LaBatre, AL; Chicksaw Bogue, AL; Windmill Point, Wachapreague, VA. • Two hydro stations installed for Elizabeth River (LafeyetteRiver and Western Branch) and data collected and data comparison performed. • The comparison analysis between MWWL and the standard sensors (one Acoustic and one pressure) showed mean differences of less than 0.02 m in the 6-minute data with standard deviation of less than +/- 0.01 m.(#) • The differences in monthly mean tabulation products showed less than 0.02 m differences. (#) • The mean differences in the tabulated times of the high and low waters were within 0.1 hour. (# “Microwave Data Processing for 9999972 Lafeyette River and 9999939 Western Branch, Edgar Davis, May 10, 2011” ).

12. Typical MWWL Gauge Installation

13. Microwave Radar SensorDAA Waterlog H-3611i Sensor Sensor and mount • Non-contact, remote sensing capability requires significantly less hardware • Easier and less costly to install than the acoustic or pressure sensors • Reduced maintenance costs • Level directly to zero of sensor • Excellent performance in enclosed, low wave energy environments One complete system Primary and Redundant systems Credit: Tom Landon and Robert Heitsenrether

14. Example - Mobile Bay Storm Surge Project MW Radar Sensor as Primary and redundant mounted on bridge walls MW Radar Sensor mounting plate w/ leveling target Credit: Tom Landon and Robert Heitsenrether

15. Example - Mobile Bay Storm Surge Project Two independent systems on each bridge; radar sensor used for both primary and backup Dog River Bridge East Fowl River Bridge West Fowl River Bridge Credit: Tom Landon and Robert Heitsenrether

16. Example - Mobile Bay Storm Surge Project Installed Oct/Nov 2011 Bayou La Batre Bridge Chickasaw Creek Hybrid design incorporates aluminum frames built for the original designs MW radar primary sensor with pressure backup sensorof 25 feet. Credit: Tom Landon and Robert Heitsenrether

17. CO-OPS MWWL Activities – Summary • Based upon the limited acceptance report and the additional testing done, CO-OPS has started implementation of MWWL sensors into operations for both NWLON operations and NOS hydrographic and shoreline survey operations. • CO-OPS has developed a preliminary environmental assessment process for determination where SD threshold conditions exist that would limit the deployment of MWWL sensors for operational purposes. • Based upon these criteria, CO-OPS will make a determination as to the appropriateness of the use of MWWL sensor for each tide station location required for upcoming hydrographic and shoreline surveys and CO-OPS will provide this information to OCS and NGS during the survey planning stages.

18. Questions? Thanks.

19. Backup Slides (1) MWWL Gauge Costs – Short Term Station (2) Sample Environmental Site Assessment – Watchapreague, VA

20. MWWL Gauge Costs – Short Term Station

21. Ideas on Using Physical Characteristics to Derive Coastal Classification System Parameters Physical Characteristic CCS Parameter Average Significant Wave Height Average Significant Wave Period Storm Frequency Occurrence 2D Fetch Distance Mean Tidal Range Diurnal Tidal Range 1st Difference for 6 min water level Air Temperature Sea Surface Temperature Salinity 1. Likelihood of increased MWWL Measurement Error 2. Max Range and Max Rate of Range Change 3. Likelihood of Ice Formation at Sea Surface 4. Likelihood of increased Aquatrak Measurement Error Air-Sea Temp Gradient Lowest observed sea level Average Vertical Density Gradient (dρ/dz) 5. Likelihood of well silting 6. Likelihood of increased Bubbler Measurement Error

22. Scaled Maps with Distance Legend - Boundary Conditions and Fetch CCS Parameter 1. Likelihood of increased MWWL Measurement Error

23. Scaled Maps with Distance Legend - Boundary Conditions and Fetch CCS Parameter 1. Likelihood of increased MWWL Measurement Error

24. Scaled Maps with Distance Legend - Boundary Conditions and Fetch CCS Parameter 1. Likelihood of increased MWWL Measurement Error

25. Standard Deviation of 1 Hz Aquatrak Record – Surface Wave Indication CCS Parameter 1. Likelihood of increased MWWL Measurement Error

26. Mean Tidal Range, Diurnal Tidal Range, and Water Level Rates of Change CCS Parameter 2. Max Range and Max Rate of Range Change Watchapreague Average Tides Mean Range – 4.02 ft Diurnal Range – 4.51ft

27. Standard Deviation of 1 Hz Aquatrak Record – Surface Wave Indication