Scoping of Flood Hazard Mapping Needs for Belknap County, New Hampshire
Abstract
This report was prepared by the U.S. Geological Survey (USGS) New Hampshire/Vermont Water Science Center for scoping of flood-hazard mapping needs for Belknap County, New Hampshire, under Federal Emergency Management Agency (FEMA) Inter-Agency agreement Number HSFE01-05X-0018. FEMA is embarking on a map modernization program nationwide to: 1. Gather and develop updated data for all flood prone areas in support of flood plain management. 2. Provide maps and data in a digital format for the improvement in the efficiency and precision of the mapping program. 3. Integrate FEMA's community and state partners into the mapping process. One of the priorities for FEMA, Region 1, is to develop updated Digital Flood Insurance Rate Maps (DFIRMs) and Flood Insurance Studies (FIS) for Belknap County, New Hampshire. The information provided in this report will be used to develop the scope for the first phase of a multi year project that will ultimately result in the production of new DFIRMs and FIS for the communities and flooding sources in Belknap County. As of 2006, the average age of the FEMA flood plain maps in Belknap County, New Hampshire is 19.9 years. Most of these studies were computed in the late 1970s to the late 1980s. However, in the ensuing 20 30 years, development has occurred in many of the watersheds, and the rivers and streams and their flood plains have changed as a result. In addition, as development has occurred, peak flooding has increased downstream of the development from increased flows across impervious surfaces. Therefore, many of the older studies may not depict current conditions nor accurately estimate risk in terms of flood heights. Belknap County gained 5,222 residents between 2000 and 2005. This represents a growth of 9.3 percent compared to 6.0 percent for the state as a whole. Belknap County ranks first (from highest to lowest) out of New Hampshire's 10 counties in terms of rate of population increase.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2006
- Accession Number
- ADA454062
Entities
People
- Robert H. Flynn