Coastal Management

Planning for sea level rise requires some use of predictive models. How high will water get? What areas will be impacted and when? Many current models are relative coarse and lack local scale detail so important for communities dealing with long term planning challenges. With advances in high resolution mapping, an unprecedented amount of detail can now be included into these models and the results vastly improve how communities can use this information. With sea level rise predicted on the order of one to two meters along the east coast of the US, very accurate elevation models derived from airborne LiDAR have the potential to significantly change how model results are presented.

However, the standard for current LiDAR data deliverables does not account for the unique hydrologic requirements of sea level rise predictions and can result in models that significantly under predict potential impacts. How is this possible? The sensor technology maps the ground surface at very high resolution, but culverts that allow water to pass under roads and railroads are not mapped in the terrain, so these crossings end up looking like dams as water seeks to find pathways to move. Ensuring hydrologic continuity through culverts and under small bridges is critical to the performance and accurate prediction of such models.