Geodetic Committee Minutes for 06/03/2009

The Geodetic Committee meeting opened at 1:00 PM June 3 2009. In attendance were Roger Patocka (Emmett County), Steve Milligan (IDOT), Gary Brown (GB Consulting), Dan Corbin (DC Inc.), Dave Croll with Amy (City of Johnston), Steve DeVries with Matt (Iowa Counties Engineers Service Bureau) and Lawrence Hartpence (City of West Des Moines). The meeting attempted a conference call which proved problematic. Those on the conference call were Alice Welch (IDOT), Dave Zenk (NOAA) and Jon Lubke (Winneshiek County). Dave Zenk shared his thoughts on the Geodetic Monument Repository, Height Modernization and a repository for Land Corners. He cautioned of the work involved in maintaining a Geodetic Monument database because of the number of monuments out there and how often they are removed. He mentioned the benefits of hosting such on a website other than the National Geodetic Survey’s: this would make it easier for users to find documentation on select monuments because the NGS database is large and may be hard to navigate. Height Modernization is more critical to Iowa now that Iowa has a Real Time Network. Dave also shared Minnesota’s success with implementing a webite to serve landcorner information. Minnesota’s website is http://olmweb.dot.state.mn.us. Steve Milligan provided a report of the progress of the IaRTN. The network does experience downtime, some planned and other unplanned. Efforts have been made to lessen the effects of planned outages by performing updates Saturdays evening to Sunday mornings. Over all, the network is becoming more stable being up 98% of the time in April. In January, it was up 78% of the time. In checking accuracies from the RTN with established monuments, there have been significant vertical inaccuracies found. This is due to inaccuracies in the Geoid. This exemplifies the need for Iowa to engage in Height Modernization. Leica is working on serving a map on the web that would show in real time the status of each station. They also are working to provide a public ftp site to obtaining files for post processing easier. The IaRTN website may be found at http://www.iowadot.gov/rtn/index.html. The next item on the agenda was the Geodetic Monument Repository. We currently have data from 6 counties. Steve and Mat from the County Engineers Service Bureau were in attendance because the hope is that the Service Bureau would be willing to host this site. Steve made it clear that the Service Bureau was interested in helping, but wanted to know the vision for this repository especially in regards to what we want the Service Bureau to be responsible for. The Service Bureau did not want to be overburdened with maintaining a site that would constantly need updated nor do they want to responsible for the accuracy of the data. This project also must be aligned with the mission of the Service Bureau. Though there were many ideas where the project could lead in the future, for now the database would be confined to monuments set by county governments, would have minimal fields: ID, Location X and Y (either in Latitude / Longitude or State Plane), a field linking to a tie sheet, and a field showing the owner of the monument. As a side note, there was mention of the work SLSI was doing to get legislation to more heavily fine individuals who destroy government monuments. In the end, the Service Bureau agreed to build a site with the 6 counties’ data they have as a proof of concept. When it is up, members of the Geodetic Committee will explore it and provide comments. After this, the site will be advertized to the county engineers. We will see if we can get them to buy into the concept. Next topic was Height modernization. DOT has decided to explore the idea. They will research this probably more towards winter. This is not a cheap endeavor: Wisconsin spent over $4 Million on their Height Modernization. The final topic discussed was building a repository for landcorners. Jon Lubke has an Americorps intern for 450 hours and thought this would be a good project for this person. It was thought that though this is a good idea, now is not the time. It would work better to build the Geodetic Monument database and then if this gains support, there will be more resources to build a landcorner database. The landcorner database needs great amounts of support because it will need much maintenance. The intern might be better used in helping with the Geodetic Monument project.