Mapping Missouri’s Lake of the Ozarks
Missouri’s largest lake, Lake of the Ozarks, is an outdoor enthusiast’s paradise. Located in the heart of the state, the 58,000-acre lake and surrounding area offer sailing, boating, water skiing, swimming, and excellent fishing opportunities, as well as hiking, biking and horseback riding. Thousands of families make the lake their vacation destination year after year.
Amid the many pleasurable activities the Lake of the Ozarks hosts is the routine work performed around it for zoning, surveying, environmental, ecological and other studies. From February 1999 to December 2001, three entities needed to gather data on Lake of the Ozarks; one for the federal re-licensing of a hydroelectric plant, one for tax purposes, and another for a floodplain study. Although their end needs were different, the three realized that by combining their projects into one study, they could enjoy efficiency and cost savings.
The PlayersAmerenUE (formerly Union Electric) is Missouri’s largest electric utility, operating nine power plants and providing energy services to 1.2 million electric customers in eastern Missouri. One of the properties it operates is the Osage Power Plant located on the Osage River in Missouri. In 1931, Union Electric built Bagnell Dam to harness the river’s power and provide electricity to the area; the dammed water subsequently created Lake of the Ozarks.
As the operator of a hydroelectric power plant, AmerenUE is subject to regulation by the Federal Energy Regulatory Commission (FERC), a regulatory agency within the Department of Energy that, among other things, licenses and inspects hydroelectric projects, ensures dam safety, and oversees environmental matters related to natural gas, oil, electricity and hydroelectric projects. The Osage Power Plant is up for re-licensing—licenses are issued for between 30 and 50 years—and AmerenUE needed geospatial data to prove to the FERC that it had properly monitored the shoreline of Lake of the Ozarks, managing pollution and water quality, protecting wildlife habitats, and controlling Osage River discharge water and water levels in the lake upstream. In addition to gathering data for its reporting requirements, administrators of the utility wanted to improve its permit tracking system and also devise a way to determine status, condition and use fees for shoreline facilities such as boat ramps, boat docks and seawalls on the lake.
Camden County, in which part of Lake of the Ozarks rests (the lake also spans Miller, Morgan and Benton Counties), has grown by more than 7,000 people in the last decade. Although county tax maps were kept current, the significant population increase was making this task increasingly difficult. To become more efficient, county officials decided to automate the process through the establishment of a Geographic Information System, or GIS.
Another party involved in the project, the Kansas City District of the U.S. Army Corps of Engineers (COE), needed to conduct a floodplain study at Lake of the Ozarks to fulfill its responsibility of monitoring flood hazards. Results from the study would help the COE advise people who live and work in the floodplain of the best actions to take to reduce potential flood damage.
Following a qualification process, Camden County selected Sanborn Map Company Inc. of Pelham, N.Y., to aid in the needed work.
Getting StartedA great deal of time was spent planning the lake project, which encompassed over 390 square miles and involved GPS control surveying, aerial photography, scanning, aerial triangulation, planimetric and topographic mapping, generation of digital orthophotography, parcel map conversion services, and ultimately, GIS application development.
Sanborn’s surveying team began by establishing and targeting 237 ground control positions to maintain data accuracy. A control network was established for the project through the use of rapid static GPS surveying techniques with Trimble 4000 SSI receivers (Trimble, Sunnyvale, Calif.). The resultant control was converted into the Missouri State Plane Coordinate System, Central Zone, NAD83 and referenced to NAVD88 vertically.
From AboveAerial photography for the project consisted of black and white exposures covering the entire project area. The photography was acquired with Sanborn’s Leica Geosystems RC-30 precision aerial camera (Leica Geosystems, GIS & Mapping Division, Atlanta, Ga.) operating out of the company’s Cessna T206 aircraft. The ASCOT ABGPS controlled flight and exposure station control system was used to ensure that the photography would be acquired at precise locations, which would in turn ensure the accuracy of the final photography.
Due to the project participants’ varying data requirements, several different scales of photography were acquired. To support the generation of 1"=100'-scale planimetric mapping, 2-foot contour and 1"=100'-scale digital orthophotography, 1"= 833'–scale black-and-white aerial photography was acquired. Black-and-white aerial photography at a 1"=1667' scale was further acquired to support the generation of 1"=200’ scale planimetric mapping, 4-foot contours, 1"=200' digital orthophotography and 1"=400' digital orthophotography. Aerial photography collection took three days.
After the aerial photography was collected, it was processed, inspected and printed. Contact prints and film diapositives for stereo compilation were generated. To support the generation of the digital orthophotography, the aerial film was scanned at 14 microns on Sanborn’s Leica Geosystems DSW500 photogrammetric scanner.
Aerial triangulation was performed using conventional hard copy means. Film diapositives were pugged (marked) and measured. All photo measurements for the triangulation process were made on first-order IMA stereoplotters at Sanborn. To ensure accuracy, all triangulation measurements were made twice and the resultant average was used in the adjustments. Fully analytical triangulation adjustment software by JFK Inc. of Indialantic, Fla., was used to make the final adjustments of the photo measurements to the ground control.
Compilers used first-order analytical stereoplotters to perform stereo compilation to generate digital elevation and planimetric data for the project. A digital elevation model consisting of mass points, breaklines and spot elevations was generated to support 2- and 4-foot contours from the photography. In addition, 100'- and 200'-scale planimetric features were digitized. Planimetric and topographic files in AutoCAD format were then delivered to the appropriate project participants.
In addition to the base planimetric and topographic datasets, black and white digital orthophotography was developed over the project area using Sanborn’s Ortho-Kork software. The resulting orthophoto images were tiled into 3,000' x 3,000' files in .cot and .tif formats on CD-ROM. Approximately 1,200 quarter section tiles were required to cover the project area.
With the photogrammetric portion of the project complete and with digital orthophotography available, technicians could begin the conversion of the shoreline parcel maps. Using the digital orthophotography as a base, 649 existing parcel maps in Camden County were scanned and warped. The final deliverables for this portion of the project consisted of new mylars for the county and digital files in AutoCAD and MicroStation formats.
The final portion of the project was the design of a GIS database and custom application to track the shoreline improvements and aid in the application and permitting process at AmerenUE. AmerenUE also wished to use the data gathered to determine use fees for boat docks and boat ramps based on square footage calculations. All GIS applications were implemented in GeoMedia (Intergraph Mapping and Geospatial Solutions, Huntsville, Ala.).
Data Conversion ChallengesWhen it came time to rectify AmerenUE ownership data with county records, Sanborn technicians faced an interesting challenge. Much of the information from the two sources did not match or was outdated. Because currency of the datasets was a significant problem, Sanborn technicians spent a great deal of time matching county ownership records with Ameren records. And the fact that Lake of the Ozarks spans four counties made records review even more difficult since the quality of information varied by county. During the course of the project, four different sets of land records, county jurisdictions, tax assessments and parcel records had to be reviewed. Sanborn technicians sent teams to do on-site scanning of county tax maps; while some counties had digital maps, others were able to supply only hard copies. Another challenge was in locating the sites geographically. Many addresses were not good and required the review of data such as legal descriptions and section, township and range to establish an accurate match.
“We spent the bulk of the project sorting through existing records and bringing everything up to date, rectifying county records with AmerenUE data,” says Steve Kasten, Sanborn project manager on the Lake of the Ozarks project. “In the end it was worth it. All the data is now organized and readily accessible. AmerenUE’s permit tracking program is much more efficient as a result.”
With the information gathering phase of the project complete, the workers moved on to the next challenge: finding somewhere to put it all.
Keeping CurrentIn the course of the two-year project, AmerenUE realized that the lake’s 20,000-plus shoreline facilities and 35,000 parcels were especially dynamic; that is, people were constantly moving and adding docks, selling and buying parcels, etc. Unless the utility put in place a system to track the changes, its data would be outdated by the time the system was set up. Utility officials decided to have Sanborn personnel perform photogrammetric updates every other year. Sanborn administrators then proposed a data maintenance desktop system to keep track of the changes. Ameren was pleased with the proposal and the project moved ahead.
From Desktop to WebAt this stage, Sanborn enlisted the help of Pellegrino & Associates (now Trailhead GIS) of St. Charles, Mo., to develop a desktop GIS application to integrate the shoreline facilities with property parcels in the four counties, and relate the parcels to AmerenUE’s proprietary shoreline information management system, or SIMS. A document management system developed in-house, SIMS had worked well for Ameren in the past, but had its limits. As a tabular system, users could not review properties spatially. Ameren wanted to organize this information and portray it geographically so it would be more useful.
What started out as a desktop application in prototype quickly moved to a web-based application once Trailhead GIS realized the extent of the data. “Lake of the Ozarks is a vast property,” says Steve Seibert, systems manager of Trailhead GIS. “At present there are about 35,000 parcels on the lake, and we had all kinds of data: orthophotos, property conversion data, facilities data—way too much information to manage on a desktop.”
Trailhead GIS developed a web-based solution in which AmerenUE employees could access the data as needed through a secure website. Implementing the web-based application included the integration of all photogrammetrically generated mapping products, the conversion of county-based property mapping, and the existing facilities permit datasets. The finished application provides a single point production database for update and maintenance, accessible through standard web browsers using off-the-shelf GIS software products. A custom-designed interface allows AmerenUE to easily access and query the application.
Sanborn and Trailhead workers also realized they needed an application service provider—a partner to house the data—since the two companies were not equipped to handle an application of this size. “When we received responses to our inquiries for data hosting, the costs were prohibitive,” Seibert says. The solution was to create a data center at Trailhead GIS. Seibert added dedicated servers and firewalls, and Trailhead became responsible for monitoring the system and keeping it online. The company set up a secure site to protect AmerenUE’s privacy and a 24-hour, seven-day-a-week Help Desk to ensure its smooth operation.
Although web-based hosting was in its infancy, Seibert ran into few snags while setting up the system. “We were challenged when aligning and integrating or normalizing datasets because we were indexing the SIMS database from a non-geographical standpoint into a geographic one. Thousands of hours were spent relating SIMS data to GIS, but the end result was worth it,” Seibert says.
Pleased with Trailhead’s work, AmerenUE put the company in charge of data maintenance. Trailhead would be responsible for integrating and maintaining property and parcel information that it received from each county and uploading and verifying permitted facilities information that AmerenUE would send from SIMS.
GIS at LastNow that AmerenUE’s web-based system is in place, the utility is enjoying greater efficiency. Rather than trudge through the field, employees are able to identify existing problems with the click of a mouse.
The new system can be used as an orthophoto locator, allowing a user to query on a section number or USGS quad name and pull up all orthophotos for the area.
AmerenUE isn’t the only entity to benefit from Trailhead’s pioneering approach to data management. The company created a scaled-down version of the application for the county assessors in the four-county project area as well. Assessors are able to access properties in the county for review purposes.
Where it once had a manual system, Camden County now has copies of all of its digitized tax maps and is using the data to automate its system. In return for its orthophotos, Sanborn provided the digitized maps so that the county can build a GIS.
The Kansas City DOE’s floodplain study was successful. As a result it is better equipped to offer advice in case of a flood at Lake of the Ozarks.
Ultimately, by joining together, each entity was able to efficiently and effectively gather the data it needed. As an added benefit, the three realized significant cost benefits, saving between 25 to 30 percent over what they would have paid had they taken on their projects separately. The routine studies were carried out successfully and tourists continue to benefit from the splendors of Lake of the Ozarks.