Track: Database Management and SDE
Implementing an Enterprisewide GIS: The Maine Department of Environmental Protection
Christopher Neal KrootThe Maine Department of Environmental Protection (MDEP) has been working on implementing an enterprisewide GIS for the last eight years. The MDEP has one main office and four regional offices in the State of Maine. The MDEP has 110 potential GIS users. These users work in all areas of environmental protection, regulation, and enforcement. The MDEP has been limited in the past to the number of users it was able to serve GIS data to. The MDEP had been storing GIS data in Esri ArcInfo LIBRARIAN software as well as in shapefiles. The MDEP main attribute data are stored in Oracle. The MDEP users primarily use ArcView GIS and its extensions for their GIS work. Using ArcInfo LIBRARIAN we were able to serve data to only a small number of simultaneous users in our home office. We were unable to serve data to our regional offices over the State of Maine wide area network (WAN). The MDEP implemented Spatial Database Engine in November 1997. The MDEP has loaded all the State of Maine GIS base data into SDE. The MDEP has also loaded many secondary data layers into SDE. The MDEP has found that the data access time for users in our main office has improved by a factor of 10. For example, accessing one data layer took 100 seconds using ArcInfo LIBRARIAN and using SDE it took ten seconds. Even more important the MDEP can now provide data access to our regional offices over the State WAN. Our experience so far shows very little performance degradation with an increase of simultaneous users. The MDEP used to have to have copies of GIS data stored on a server in each of our regional offices. Now, with SDE the MDEP can serve data to our regional offices from the SDE server in our main office. In the past with ArcInfo LIBRARIAN, the GIS server would bog down with six simultaneous users. Now with SDE the GIS server does not bog down with twelve simultaneous users. The MDEP is still in the process of implementing SDE and converting our custom ArcView GIS applications to access data in SDE. We are expecting to increase the number of users and also to provide public access to GIS data using SDE in 1998.
Christopher Neal Kroot
ME Dept of Environmental Protection
State House Station # 17
Augusta, ME 04333
USA
Telephone: 207-287-6167
Fax: 207-287-7896
E-mail: ess christopher.kroot@state.me.us