Snohomish County 9/27/2024 Amendment 1

surface artifacts from being created between mass points and break line vertices. The proximity threshold for reclassification as Ignored Ground is at the discretion of the data producer, but in general will not exceed the aggregate nominal pulse spacing (ANPS). • Streams, rivers, and water bodies meeting the criteria for hydro -flattening will be monotonically continuous where bridge decks have been removed. • Any break lines used to enforce a logical terrain surface below a bridge will be considered a required deliverable. Digital Surface Model (DSM) product will have same resolution, format and tiling specifications as the Raster DEM. Break Lines: • Break lines for all hydro -flattened areas will be delivered, regardless of technique used for hydro -flattening the DEM. • Break lines will be delivered in ESRI file geodatabase formats, as PolylineZ and PolygonZ feature classes, as appropriate to the type of feature represented and the methodology used by the data producer. • Break lines will be developed to the limit of the buffered project boundary area. • Break lines will be delivered in the same coordinate reference system and units (horizontal and vertical) as the Lidar point delivery. • Break line delivery may be in a single layer or in tiles, at the discretion of the data producer. • In the case of tiled deliveries, all features will edge -match exactly across tile boundaries in both the horizontal (x, y) and vertical (z) spatial dimensions. • Delivered data will be sufficient for the USGS to effectively re-create the delivered DEMs using the Lidar points and break lines without substantial editing. Intensity Image • 1.5 U.S. Survey Feet cell size • Intensities 16-bit, linear rescaled • Image 8-bit, 256 color gray scale and GeoTIFF format • Images will be tiled to match the Classified LAS and DEMs. Swath Separation Images Delivery Diagram: A final project -wide delivery diagram is required for QL1 projects over 1,000 square miles. At the completion of acquisition NVSG, Inc. will supply a diagram delineating the delivery blocks. Metadata: Task Order requirements will be met and generally include: • Ancillary products used to support processing of the Lidar dataset will be delivered. • Collection Report detailing mission planning and flight logs. Additionally, a flight index will be delivered as an ESRI file geodatabase. Flight index will contain flight line ID, acquisition date, start time and end time for each flight line. • Georeferenced, polygonal extents detailing actual coverage of each of the Lidar swaths will be delivered as defined in the referenced Version 1.3 specification. Esri geodatabase is required. • Survey Report detailing the collection of control and reference points used for calibration and QA/QC. • Processing Report detailing calibration, classification, and product generation procedures including methodology used. Page 1 5