Enhance Your Terrain Model

We optimized our USGS compliant hydro-flattening process, suitable for all LiDAR-based Digital Terrain Models (DTM)

We Make Your DTM Ready for Analysis and Modeling

We make your DTM ready for analysis and modeling

All water surfaces of digital elevation models (DEM) generated based on remote sensing data do not represent measured heights and have to be post-processed. By flattening the water surface and matching it to the surrounding terrain, DEMs are made applicable for applications.

This hydro-flattening procedure is a time-consuming process. We support companies to achieve this important step on time and according to the specification.

Our highly accurate, well-proven and robust hydro-flattened process can be applied to all LiDAR based Digital Terrain Models. The process is ideal for handling large-scale projects consistently and delivers results with high accuracy. The hydro-flattening is performed according to USGS Lidar Base Specification Guidelines. The results fulfill the USGS National Geospatial Program’s (NGP) requirements and can be integrated into the NED.

Key Hydro-flattening DTM Services

Premium service

Our sophisticated hydro-flattening process meets highest quality requirements and is optimized for time efficiency.

Big data processing

Our deep technical and operational experience enables us to manage large projects and quickly produce hydro-flattened DTMs over vast areas.

Quality assurance

We understand USGS requirements and LiDAR specifications. Our QA and QC procedures ensure high-quality results.

Flexible with model customization

We recognize the importance and challenge of high-quality requirements and demanding delivery schedules. On-spec, on-time delivery is our priority.

How It’s Done

VeriDaaS’ produces hydro-flattened DTM based on any LiDAR point cloud in accordance with the USGS Lidar Base Specification Guidelines.

In our hydro-flattening process, we digitize the perimeter of waterbodies, lakes and river shorelines and create river centerlines using intensity and ortho images. Additionally, we select all man-made features such as bridges and dams that affect the hydrological flow.

LiDAR points that fall within the water features are extracted and elevations (Z values) for the water features are determined and assigned. Feature Type and Class are captured along with the X, Y, and Z attributes.

The hydro-flattened DTM process is followed by an independent quality control including content and accuracy check.

The following water bodies are considered in the hydro-flattening process:

  • Lakes, Reservoirs and Pond with a size of ≥ 0.8 hectare (= 8000 m²; 2 acres) are flattened to one water surface level.

  • Streams, Rivers, Canals – all streams with a nominal width of ≥ 30 m are flattened to a single elevation value from bank-to-bank and sloped downhill following the surrounding terrain.

  • Oceans including tidal waterbodies such as seas, gulfs, bays, inlets, salt marshes, and large lakes are flattened for each different water surface elevation. All ocean features are set to 0 m (Geoid projection).

All permanent islands with a size of ≥ 1 acre (4000 m²) in all waterbodies are maintained as land. Smaller islands are neglected and considered as water in all waterbodies.