ENHANCEMENT AND EXPANSION
Selected Perspectives: As of Spring 2009, all but five percent of reservoir-survey data in RESSED are from the period 1930-1990. New data are being added to a temporary off-line database as they become available and are quality checked, before being added to RESSED. It is possible that additional bathymetric-survey results exist for the current 1,823 reservoirs before 1994, and probable that some of these reservoirs have since been (or will be) re-surveyed. Some of the reservoirs included in the RESSED database no longer exist.
About 79,000 dams are listed in the National Inventory of Dams (NID). About half of the reservoirs listed in Spring 2009 version of RESSED also are listed in the NID. If bathymetric-survey data exist for but ten percent of NID reservoirs that are not cross-listed in RESSED, compilation and entry of these data would increase the number of RESSED reservoirs by about 4-fold to about seven thousand.
The March 2009 version of RESSED represents about 0.03 percent of U.S. impoundments (Simley, 2007), as determined by the EPA/USGS National Hydrography Dataset (NHD). This statistic further illustrates that the present RESSED database – albeit the largest single programmatically based reservoir survey database available for the United States (U.S.), according to the Subcommittee on Sedimentation – contains data representing only a relatively minuscule number of U.S. impoundments.
Anticipated Short-Term Future Activities: In recognition of the importance of reliable water supplies for the Nation, quantification of rates at which the nation’s impoundments are losing capacity is considered a high priority by the Subcommittee on Sedimentation. To this end, the Subcommittee is developing plans to enhance and expand the RESSED database. Enhancements include adding improved reservoir location information, and additional bathymetric-survey data for existing reservoirs. Expansion of the RESSED database focuses on adding reservoirs and related bathymetric data.
The Subcommittee is cognizant of the fact that the Spring 2009 RESSED database structure is archaic and not amenable for capturing all pertinent reservoir survey data produced by the today’s technologically advanced instruments and methods. The RESSED workgroup of the Subcommittee plans to convene an “expert panel” comprised of those with expertise in reservoir surveys, database design and management, and HTML programming. The primary goals of this expert panel will be to:
- compile protocols for reservoir surveys and to identify those that might be recommended for use by the Subcommittee
- recommend an architecture for a robust reservoir database to meet the needs of the Nation in the 21’st century; and
- identify potential funding sources and mechanisms to develop and post online the new database structure with supporting protocols.
As yet there is no timetable for this unfunded expert panel to accomplish these goals.
Perspective on Spreadsheets (Excel) versus Relational Databases (Filemaker Pro/RESSED): The RESSED programming team has fielded queries on the future anticipated capability for public updating of RESSED. A decision has been made to accomplish public data entry -- when appropriate support is secured for this purpose -- by means other than porting spreadsheet data to RESSED. Click here for an explanation of the differences between a spreadsheet and a relational database and the fundamental incompatibility associated with trying to to use the former to update the later.
