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These data are the lidar points collected for FEMA Risk Mapping, Assessment, and Planning (Risk MAP) for the Merrimack River Watershed. This area falls in portions of Hillsborough, Belknap, Merrimack, Rockingham and Strafford counties in New Hampshire and portions of Essex, Middlesex and Worcester counties in Massachusetts. Using a Leica ALS60 LiDAR system, a total of 268 flight lines of high density (Nominal Pulse Spacing of 1.0 m) were collected over the Merrimack area which encompasses 1302 square miles. A total of 19 separate lifts were flown on November 11th, 12th and 13th and December 19th and 29th, 2011 and January 7th and 11th in 2012. One airborne global positioning system (GPS) base station was used to support the LiDAR data acquisition: FIT B. The data were received by the NOAA Office for Coastal Management from NH GRANIT. For data storage and Digital Coast provisioning purposes the data were: 1. Converted from UTM Zone 19, meters, NAD83 to geographic coordinates. 2. Converted from NAVD88 (Geoid09), meters to ellipsoid heights, using Geoid09 3. Converted overlap points that were classified as 11 to class 12 (Overlap). Data available for download from the Digital Coast include the following classifications: 1. (Unclassified) 2. (Ground) 7. (Low Point Noise) 9. (Water) 10. (Ignored) 16. (Withheld for ASPRS Definition, original data classed as 11, moved due to Digital Class use of class 11) 17. (USGS Overlap Default) 18. (USGS Overlap Ground)