1) Project Status

One goal of this project is to develop and standardize a centerline coverage of the road network for the State of Alaska through a cooperative effort from all groups currently using and or maintaining transportation data.

The first step for this project was to research and contact agencies or groups that are currently working with transportation layers within the state. Phone interviews were conducted with the various agencies. It was determined that, out of the fifteen (15) organized boroughs and municipalities within the state, eight (8) are currently using o r have a transportation layer as some part of a GIS or automated mapping system.

All of the boroughs, municipalities, corporations and government agencies that maintain these transportation layers, as well as groups who might have an interest in transportation data, were invited to attend a meeting/workshop for the Transportation Coordination Project held during the Alaska Surveying and Mapping Conference in February 1999.

A survey was also sent to each group to help document the data sets they maintain. To date only five (5) responses have been returned. Another request for completed surveys has been sent.

After introductions and brief descriptions by the boroughs on their related data, it was discovered that a majority of the data sets are actually tax based maps which show parcel data and road right of ways (ROW). Questions then arose on how to create centerlines from these data sets and the usefulness of centerlines for their tasks.

The Alaska Department of Transportation and Public Facilities, Division of Statewide Planning, Statewide GIS Mapping Section gave a presentation on a multiyear cooperative effort they are performing in conjunction with the Statewide Traffic Data Section to collect road centerlines using Differential GPS. Prior to the framework meeting, sample data from DOT&PF GIS Mapping Section DGPS project was sent to USGS for their review and evaluation. At the meeting USGS gave a brief description on their evaluation of this data. They indicated that they were quite pleased with the quality of the data and that they intend to utilize it for updating the transportation layers for all scales of their quadrangles (1:250,000, 1:63,360 and 1:25,000). DOT&PF Statewide GIS Mapping Section will make all the data they collect and process available to USGS for this purpose.

During the workshop further discussion was held on the accuracy of the data sets which led to assorted issues and concerns about the data and its collection. Some of the boroughs questioned their need for a centerline coverage. DOT&PF Statewide GIS Mapping Section stated that the use of centerline files will allow users access to numerous databases throughout the DOT & PF that store various information on the road network.

The boroughs that did not carry centerlines in their data indicated that they had no plans to create centerlines or the time to do it. We discussed ways to convert existing data sets to a centerline coverage. No easy or proven technical solutions were presented.

Agencies interested in participating further in the enhancement of a transportation data layer became members of the AGDC Transportation Subcommittee.

• We have been able to bring together a majority of the parties that maintain or have interest in transportation data for the state.
• A working relationship with these entities is being strengthened as the project proceeds.
• An excellent cooperative working relationship has been established with the USGS.
• Data from the DOT&PF Statewide GIS Mapping Sections DGPS centerline project was provided to USGS for their review and evaluation, which produced very favorable results.
• A means for collecting data and the unique identifier to be used was developed by the DOT&PF Statewide GIS Mapping Section and is solidly in place.
• A library of data used and maintained by the different organizations is being created.
• A data distribution system is being planned by DOT&PF Statewide GIS Mapping Section using Internet mapping technology from ESRI.

One of the big issues affecting this project at its onset was the ability or means to create centerline data from existing data sets. Much of the data is parcel based and displays road ROW. Road centerlines would have to be created from these. Evaluation of this process to date indicates this is a time consuming process with variable results. The Department of Natural Resources intends to investigate conversion of 2-sided borough parcel data into a centerline using a process that completes the conversion programmatically. This process was not available at the time of the original evaluation.

DOT& PF's Statewide GIS Mapping Sections DGPS centerline project offers the best centerline data available at this time. They are in their third year of data collection. Data processed so far has received full approval from the U.S.G.S. While data collection continues, methods to enhance and accelerate data cleanup and processing are being pursued.

DOT& PF's Statewide GIS Mapping Section has been successful in extracting limited amounts of data from the Highway Analysis System (HAS). However, HAS is undergoing a system wide evaluation, the outcome of which has yet to be published. Major changes in HAS may change the methods and/or ability to extract data. (HAS is a statewide database containing highway related information. It is an older system. Some of the data is updated continuously and some is updated infrequently if at all.)

3) Lessons Learned

• Be Flexible The project has shifted from the original plan of using a state and local coordinating committee to work with the U.S.G.S. on development of a Framework data set. The U.S.G.S. work has given way to the DOT/PF Statewide GIS Mapping Sections DGPS project. The requirement for coordination remains. The U.S.G.S. has offered to help with technical review of the DGPS procedures and data quality assessments.
• Lots of Interest in Roads - Need to Stay Focused on the Project. The framework meeting attracted many individuals with an avid interest in transportation issues. Topics were raised that are not directly involved in the Transportation Framework Project and cannot be addressed by this project. However, they should not be forgotten. The interest in this project and the wish for a positive outcome was encouraging. Future meetings of the subcommittee must stay focused on the centerline.

4) Training Needs

Since it is unlikely that we will be attending the meeting on May 18th due to state imposed travel restrictions, we are not looking for any training to take place at that time. We will however, be seeking advice from other GIS experts on how to process the data, that is currently being collected by the DOT&PF Statewide GIS Mapping Section, in the most efficient manner.