Monitoring Storm Tide from Hurricane Sandy along the coast of New Jersey

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1 Photos courtesy of The Roosevelts, Orig. published Monitoring Storm Tide from Hurricane Sandy along the coast of New Jersey Thomas P. Suro, P.H., CFM Hydrologist/ Engineer Act. Surface-water Specialist U.S. Geological Survey New Jersey Water Science Center May 22, 2013 NJ Water Monitoring Council Meeting

2 Monitoring Storm Tide from Hurricane Sandy Background on USGS coastal-monitoring program. Storm history for Hurricane Sandy. USGS sensor deployment and recovery. High-water mark flagging and surveying. Results from Hurricane Sandy documentation.

3 Monitoring Storm Tide from Hurricane Sandy Past Storm-Sensor Deployment USGS studies effects of hurricanes and tropical storms to better understand potential impacts on coastal communities and habitats. Current storm-surge sensor deployment program began in 2005 after Hurricane Katrina. USGS deployed sensors for: Rita (2005) Wilma (2005) Ernesto (2006) Gustav (2008) Ike (2008) Earl (2010) Irene (2011) Isaac (2012) Sandy (2012)

4 Storm History and Deployment Eighteenth named storm of 2012 season; tenth hurricane of season. Formed as a tropical disturbance on Oct. 18, named on Oct. 22 (Tropical Storm), reached peak intensity on Oct. 25 (Cat 2 Hurricane). Center of Sandy makes landfall near Atlantic City, NJ at around 7 P.M. on October 29th with 90-mph winds. Prior to landfall storm began transformation to a post-tropical cyclone. Gale- to storm-force winds from Sandy, lasting 12 to 18 hours caused major to record coastal flooding along the coast of New Jersey on October 29, Landfall near Atlantic City Oct. 29 TS Oct 22 Begins to re-intensify to Cat. 1 Oct. 28 Cat. 2 Oct. 25 Begins transition to posttropical Low Oct 18

5 Storm History and Deployment Predicted unprecedented track, posttropical transition, and massive wind field (fetch), prompted USGS toward deployment. Sensor deployment needs to be decided at least 4 days before predicted landfall. By October 24 most NHC models predicted landfall along northern mid- Atlantic or Northeast coast. On October 25th USGS consults with NWS and NHC and a decision was made to deploy. Oct Landfall Oct. 28 Sensor deployment complete Oct. 26 Sensor deployment begins Oct. 25 Decision made to deploy

6 East Coast Deployment Sensors deployed by USGS along east coast from Virginia Beach, VA to Portland, ME. 230 storm-tide sensors, 65 barometric-pressure sensors, 9 wave-height sensors, 8 rapid-deployment gages, and 921 HWM s flagged. More than 14 local USGS offices and 2 storm-surge coordination centers directly involved. Development of online mapper to display real-time data and storm-tide elevation to NAVD88 within days of storm. A coordination challenge!

7 Data Collection and Sensor Recovery USGS operates 23 continuoustide gages in NJ. USGS also has 32 tidal crest-stage gages in NJ. The USGS also operates 6 streamgages in Barnegat bay 10 storm surge sensors were deployed in NJ prior to Sandy. Highest Peak storm-tide elevations recorded in Raritan Bay. > 13 ft > 9 ft > 7 ft

8 Data Collection and Sensor Recovery More than 900 high-water marks (HWMs) flagged along the east coast. About 620 were surveyed (Conn, Mass, and RI not surveyed due to lack of funding) In NJ 170 marks were collected and surveyed from Bergen to Cape May counties. HWMs verified recorded peak storm-tide elevations and added valuable information in all of NJ s coastal counties ft 9-11 ft (waves ft) 6-9 ft

9 Peak storm tide data USGS tide gage network not designed for hurricane monitoring. Data estimated when peak tide levels exceeded maximum recordable limits. HWM data collected to verify peak storm tide elevations at USGS gages and along the entire coast.

10 Peak storm tide data Peak storm tide elevations greater than 12 ft recorded in and around Raritan Bay. Peak storm tide elevations generally 8-12 ft from Sandy Hook to Toms River. Peak storm tide elevations generally 6-8 ft south of Atlantic City. Note: Peak storm tide was recorded by tide gages, surge sensors and wave sensors.

11 Flood extent and inundation USGS tide gages, storm sensors, and HWM data were used to calibrate flood extents. The USGS worked in cooperation with FEMA, NJDEP and NJDOT to develop a documentation plan for extent of flooding. Raritan Bay had highest storm tide Sandy Hook completely inundated SeaBright peak 2 ft. greater than 1992 Atlantic City worst flooding since 1962

12 Comparison to previous storms Sandy was not the first major Hurricane to Hit New Jersey and the northeast. Hurricanes in the northeast have been recorded back to the 1600 s. In 1893 back to back August hurricanes hit NJ and the northeast. In Sept the Great New England Hurricane passed along the NJ coast and made landfall on Long Island. In Sept The Great Atlantic Hurricane hit New Jersey much worse than the (winds of MPH with gusts > MPH) NOTE: Second year of hurricane reconnaissance : B25 used to fly into the storm. The March 1962 storm was the most widespread and devastating to hit the region during that century. (Named the five-high storm because of five consecutive high tides.) The December 1992 Great Nor easter was a slow-moving nor easter that produced record setting storm tides at most USGS tide stations along the coast at New Jersey and New York. (only exceeded by 1962 storm in a few locations)

13 Comparison to previous storms Sta No. Sta. Name March 1962 (ft. NAVD 88) Dec (ft. NAVD 88) Aug 2011 (ft. NAVD 88) Oct 2012 (ft. NAVD 88) Sandy Ratitan River at Perth Amboy, NJ Shrewsbury River at Sea Bright, NJ Barnegat Bay at Loveladies, NJ Little Egg Harbor at Beach Haven, NJ Mullica River at Port Republic, NJ Note: some HWM s from 1962 show ft peak storm-tide elevations south of AC to Cape May.

14 Summary of data What does this mean? Sandy reset the current standard for preparedness. New Jersey has been battered by hurricanes in the past, so we need to better prepare for the future. USGS data is being used by FEMA to verify flooding. (Sandy elevations generally 0.5 to >3 ft higher than previous record) USACE and NWS have access to the data for storm tide/surge modeling. (Peak storm-tide pattern for Sandy was similar to 1992 but different than 1962) State and local government can use the data to verify flood prone areas and inundation, peak storm-tide elevations etc.. (USGS data for Sandy available at nj.usgs.gov click link for Information on Hurricane Sandy ). The USGS is also trying to work with the Natural and Cultural Resources group at FEMA and representatives from other government agencies including NPS and USACE on the topics of coastal restoration and monitoring.

15 Access to data and reports Initial USGS storm tide monitoring report available : USGS Scientific Investigation Report for New Jersey is in progress.

16 Monitoring Storm Tide from Hurricane Sandy along the coast of New Jersey Contact Info: Thomas P. Suro, P.H., CFM Hydrologist/ Engineer Act. Surface-water Specialist U.S. Geological Survey, NJ Water Science Center 810 Bear Tavern Road, W. Trenton, NJ Ph : (609) Fax: (609)