Woolpert
20190314
CA-AZ FEMA R9 Lidar 2017 D18: Salinas QL2 AOI; Hydro Breaklines
Vector digital data
Product: Hydro breakline river and lake data as PolylineZ and PolygonZ features in an Esri file geodatabase, with bridge breaklines as PointZ features in Esri shapefile format.
Geographic Extent: Approximately 10,547 square miles across 11 AOIs in California and Arizona; approximately 6,658.2 square miles across the Salinas QL2 AOI in Western California.
Dataset Description: The CA-AZ FEMA R9 Lidar 2017 D18 lidar project called for the planning, acquisition, processing, and production of derivative products of lidar data to be collected at a nominal pulse spacing (NPS) of 0.7 meters. Project specifications were based on the U.S. Geological Survey National Geospatial Program Base Lidar Specification, Version 1.2. The data was developed based on a horizontal datum/projection of NAD83 (2011) State Plane California IV (FIPS Zone 0404), US Survey Feet, and a vertical datum of NAVD88 (GEOID12B), US Survey Feet. Breaklines are reviewed against lidar intensity imagery to verify completeness of capture. The compilation procedure included use of lidar intensity, bare earth surface model, point cloud data, and open source imagery in an effort to manually compile hydrologic features in a 2-D environment. Following the compilation phase, a separate process was used to adjust the breakline data to best match the water level at the time of the lidar collection. Any ponds and/or lakes were adjusted to be at or just below the bank and to be at a constant elevation. Any streams were adjusted to be at or just below the bank and to be monotonic. Manual QAQC and peer-based QC review was performed on all delineated data to ensure horizontal placement quality and on all adjusted data to ensure vertical placement quality. Bridge breaklines were also compiled in efforts to generate an accurate DEM product. The final hydrologic and bridge breakline products were delivered as PolygonZ features in an Esri file geodatabase.
Ground Conditions: Lidar was collected from January 22, 2018 through April 21, 2018 while no snow was on the ground and rivers were at or below normal levels. Due to a time difference of approximately one month between adjacent flight lines, there are two instances, a reservoir and a river bed, that show elevation drop-offs. Initial acquisition occurred when these features were dry, with the features containing water at the time of the follow-up flights. The feature portions that contain water were digitized, hydro-flattened, and incorporated into the DEM. In order to post process the lidar data to meet task order specifications and meet ASPRS vertical accuracy guidelines, Woolpert established 148 ground control points across all California AOIs that were used to calibrate the lidar to known ground locations established throughout the project area. An additional 258 independent accuracy checkpoints (145 NVA points and 113 VVA points), were collected across all California AOIs and used to assess the vertical accuracy of the data. These checkpoints were not used to calibrate or post process the data.
High quality elevation data products are critical for riverine floodplain study and mapping for the National Flood Insurance Program. This acquisition allows FEMA Region IX to produce floodplain analysis where it is needed, to provide updates to flood insurance rate maps, and to produce floodplain administration decision support tools.
FEMA, in administration of the National Flood Insurance Program and under FEMA's Risk Mapping Assessment and Planning (Risk MAP) program, orders these elevation products to meet or exceed the quality specifications published by the US Geological Survey for acceptance into the 3-D Elevation Program (3-DEP). Data of this quality is interpreted as sufficient for floodplain engineering studies, analysis, and mapping of flood hazard.
USGS Contract No. G16PC00022 Task Order No. 140G0218F0027. CONTRACTOR: Woolpert. Sub-Contractors: Aerial Services, Inc. (ASI), Aero-Graphics, Keystone Aerial Surveys.
Breakline File Type = GDB
Breakline Elevation Units = survey feet
Downhill Treatment Applied = Monotonic
Type of Hydro Treatment Required = Hydro-flattened
20180122
20180421
ground condition
None planned
-122.209177053
-120.193501219
37.2656391762
34.963588414
None
Model
Breaklines
Elevation Data
Lidar
None
United States
California
Monterey County
San Benito County
San Luis Obispo County
Santa Clara County
Santa Cruz County
No restrictions apply to this dataset.
None. However, users should be aware that temporal changes may have occurred since this dataset was collected and that some parts of these data may no longer represent actual surface conditions. Users should not use these data for critical applications without a full awareness of its limitations. Acknowledgement of the U.S. Geological Survey would be appreciated for products derived from these data.
The information contained in these data is dynamic and may change over time. The data are not better than the original sources from which they were derived. It is the responsibility of the data user to use the data appropriately and within the limitations of the data for which it was requested and prepared, in general, and these data in particular. The related graphics are intended to aid the data user in acquiring relevant data. It is not appropriate to use the related graphics as data. Woolpert gives no warranty, expressed or implied, as to the accuracy, reliability, or completeness of these data. It is strongly recommended that these data are directly acquired from a Woolpert server, and not indirectly through other sources which may have changed the data in some way. Although these data have been processed successfully upon Woolpert's computer system, no warranty, expressed or implied, is made regarding the utility of the data on another system, or for general or scientific purposes; nor shall the act of distribution constitute any such warranty. This disclaimer applies both to individual use of the data and aggregate use with other data.
Microsoft Windows 10; Esri ArcCatalog v10.4; Esri ArcMap v10.4; GeoCue 2017.1.14.1; IPAS Pro v1.35; LP360 v2018.1.57.4; Leica CloudPro v1.2.4; Novatel Inertial Explorer v8.60.6129; POSPac Software v5.3; TerraMatch v18; TerraModeler v18; TerraScan v18.
All data covers the entire area specified for this project. Breaklines were collected in all inland ponds and lakes ~2 acres or greater. These features were flat and level water bodies at a single elevation for each vertex along the bank. The entire water surface edge is at or below the immediate surrounding terrain. Breaklines were collected for all streams and rivers with a ~100 foot nominal width or wider. These features are flat and level bank to bank, gradient will follow the surrounding terrain and the water surface will be at or below the surrounding terrain. Streams/river channels will break at culvert locations however not at elevated bridge locations.
All files are inspected to ensure that they conform to the specified file naming conventions, all files load in their correct geographic position, all files conform to the project specifications for file standard and content.
Keystone Aerial Surveys
20190314
Lidar acquisition
Lidar point cloud
Dayton, OH
Woolpert
Digital data
20180122
20180421
ground condition
CA-AZ FEMA R9 Lidar 2017 D18 - Lidar Point Cloud Data
This dataset includes airborne lidar data point cloud data acquired as part of this task order. This data was used to create the required derivative lidar products.
Woolpert
20190314
Hydro Breaklines
Vector digital data
Dayton, OH
Woolpert
Digital data
20190314
ground condition
CA-AZ FEMA R9 Lidar 2017 D18 - Breaklines
This dataset includes hydro breaklines collected as part of this task order.
Woolpert
20190314
Data extent
Vector digital data
Dayton, OH
Woolpert
Digital data
20190314
ground condition
CA-AZ FEMA R9 Lidar 2017 D18 - Data Extent
The data extent was created in Esri shapefile format. The shapefile was buffered by 100-meters. It was used in acquisition planning and to clip the final deliverable data.
Hydro Breaklines: Class 2 (ground) lidar points was used to create a bare-earth surface model. The compilation procedure included use of lidar intensity, bare-earth surface model, point cloud data, and open source imagery in an effort to compile hydrologic features in a 2-D environment. Elevation values were assigned to all inland ponds and lakes, inland pond and lake islands, and inland stream and river islands, using TerraModeler/LP360 functionality. All ground (Class 2) lidar data inside of the collected inland breaklines were then classified to water (Class 9) using TerraScan macro functionality. A buffer of 1.14 feet was also used around each hydro-flattened feature. These points were moved from ground (Class 2) to Ignored Ground (Class 10). Breaklines are reviewed against lidar intensity imagery and surface models to verify completeness of capture. The horizontal placement of breaklines is compared to terrain features and the breakline elevations are compared to lidar elevations to ensure all breaklines match the lidar within acceptable tolerances. Some deviation is expected between breakline and lidar elevations due to monotonicity, connectivity, and flattening rules that are enforced on the breaklines. Once completeness, horizontal placement, and vertical variance is reviewed, all breaklines are reviewed for topological consistency and data integrity using a combination of Esri Data Reviewer tools. The final hydrologic breakline river and lake data was delivered as PolylineZ and PolygonZ features in an Esri file geodatabase, with bridge breaklines as PointZ features in Esri shapefile format. This breakline dataset was used in the processing of the DEM deliverable.
Two stream beds near Greenfield, CA and a part of Lake Nacimiento, are affected by a difference in water levels between adjacent flight lines. During original acquisition, the levels were lower/dry, but contained water during the time of follow-up flights approximately one month later. The feature portions containing water were digitized as hydro features. The feature portions that contain water were digitized.
CA-AZ FEMA R9 Lidar 2017 D18 - Lidar Point Cloud Data
CA-AZ FEMA R9 Lidar 2017 D18 - Data Extent
20190314
CA-AZ FEMA R9 Lidar 2017 D18 - Breaklines
Vector
State Plane Coordinate System 1983
0404
36.0
37.25
-119.0
35.33333333333334
6561666.666666666
1640416.666666667
coordinate pair
0.01
0.01
survey feet
North American Vertical Datum of 1983 (2011)
Geodetic Reference System 80
6378137.0
298.257222101
North American Vertical Datum of 1988 (GEOID12B)
0.01
feet
Explicit elevation coordinate included with horizontal coordinates
20190314
Woolpert
mailing and physical
4454 Idea Center Blvd.
Dayton
OH
45430
USA
(937) 461-5660
FGDC Content Standard for Digital Geospatial Metadata
FGDC-STD-001-1998