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APPENDIX H Database Information SUGGESTIONS FOR A NATIONAL SCOUR DATABASE Using existing databases found through the literature search and the data from the scour monitoring systems made available by the survey respondents, the following are suggestions on how a national database might be structured and what elements it might contain. Chapter 8 contains a discussion of the current U.S. databases that may be modified to include scour data for use as a national scour database. This following includes information on assembling and maintaining a scour database. Databases that served as examples included the United States Geological Survey (USGS) National Bridge Scour, the Abutment Scour (South Carolina), and the National Water Information System (NWIS) databases. Information that could be assembled in a national scour database for the scour monitoring data are outlined below. The organization of the National Bridge Inventory database could be used for the elements that both share in common. Additional elements relative to hydraulics and scour would be added in a bridge scour section. A national scour monitoring database for the scour monitoring data could contain the following elements for each bridge site: Bridge Information Name of Bridge Bridge Location Bridge Number Bridge Length Number of Spans Type of Bridge Average Daily Traffic (ADT) Year Built (and Rebuilt) NBIS Items 60 and 113 ratings Measured scour (minimum, moderate, severe) Scour Monitoring Information Type and Number of Scour Monitors Employed Installation Date of Scour Monitors StatusâActive or Inactive and Why Site Specific Information Waterway Characteristics Waterway TypeâTidal/Riverine Flow Habit Water Depth River TypeâBraided, Meandering, Straight Stream Size Bend Radius Bank Condition Floodplain Width Drainage Area Slope in Vicinity Soil Conditions Extreme Conditions (Low/Medium/High) Debris Ice Flows High Velocity Flows 152
Contraction Scour Stream Instability Documentation As-built or design plans Borings Soil classification tests Stream cross-sections Fathometer surveys Photographs Narrative information could be added about the site, the scour history of the bridge and any emergency Plan of Action. Photographs of the bridge and site might also be included. Additional information could be included in this database, such as some of the other items in the National Bridge Scour Database. At the same time, the desire for a large amount of data needs to be balanced with the need to minimize the time required of respondents, and therefore increase the number of responses. ASSEMBLING AND MAINTAINING THE DATABASE The data could be assembled much like a search engine. For example, if a person is looking for sites with predominantly clay soils in debris-prone waterways, a list of similar sites could be readily generated for comparison. A main homepage could be set up where the user is allowed to choose specific bridge, waterway, and soil characteristics to narrow down their search. The search engine would list bridge sites that match the userâs criteria in order of relevance. The user could then click on each bridge listing to view site-specific data. Links to sample data and graphs, agency information, manuals, Plans of Action, and scour monitoring vendor information could be listed as references for each bridge site. A contact name could be listed for each bridge for those who wanted to obtain more information about a particular site. This would also allow for an exchange of ideas and experiences between bridge owners, agencies and others. Those responsible for maintaining the database might update the status, agency contact information, and available references for each bridge. This information could be updated once per year. The data could be collected one to two times per year. States submit their Bridge Scour Evaluation Program data to FHWA two times per year. Scour monitoring data could be requested and submitted at the same time. Some of the survey respondents indicated that they do not intend to keep the data for any period of time. Others said they plan to keep their data indefinitely. Those maintaining the database could collect this data annually or semi- annually as well. Reminders could be sent periodically via e-mail so that the respondents could reply and add an attachment with the scour monitoring data. Other measurements taken at the site such as water stage and velocity could also be collected for the database. If possible, all data could be converted into more user-friendly formats such as tables and graphs, and used as reference material for those searching the database. Functional Applications Local Scour 153
