|
SATELLITE REMOTE SENSING: Utilities Visualize Land Information
Today's advances digital remote sensing technology is fast enabling the utility industry to solve decades-old business challenges.
By Ron Elsis How can utility companies efficiently and cost-effectively keep their land base data as accurate and timely as possible? Moreover, how can they make the information derived from those land bases as useful as possible in the planning, installation and maintenance of their utility systems?
Today's advanced digital remote sensing technology is fast enabling the utility industry to finally solve these decades-old business challenges. Made possible in part by a new generation of remote sensing satellites that will soon make 1-meter resolution space imagery available to the commercial marketplace, the digital land base allows utilities to "visualize" land information in a way never before possible. The satellite-derived digital orthoimage - the core of today's digital land base - is the key element to opening up a whole new era of possibilities for the use of space imagery in an ever-growing number of utility applications.
Why are progressive GIS managers turning to high-resolution space imagery to help them make more informed business decisions when it comes to planning, implementing and maintaining utility systems? Here are just a few of the key reasons:
• Access to Updated, High Quality Land Information - A satellite can frequently revisit and repeatedly collect imagery with consistent quality for a large geographic area. This capability enables users to identify changes within their service areas and update their digital land bases on a monthly or yearly basis. By comparison, creating or updating a vector land base using traditional data acquisition methods can take weeks or even months to collect and process the necessary information.
• Reduced Costs for Creating and/or Maintaining Land Bases - Due to the high cost associated with creating and maintaining a vector land base, many utility companies traditionally only update their land base information about every five years.
Often, by the time the update is completed, the information is already outdated. At a cost of approximately $150-$250 per square mile, users can now acquire high-resolution space imagery at a fraction of the cost of other imagery sources. Lower cost allows utility companies to update digital land base information much more frequently than in the past. This cost savings is in part achieved due to the imagery archive concept, whereby the multiple usage of stock imagery helps keep costs down to any single user. Also, a change detection analysis can be conducted as needed to update only those areas that require it, further reducing the cost of maintaining the land base.
• Ability to More Efficiently Interpret Features and Changes - With the extremely high resolution and accuracy of today's space imaging technology and the ability to acquire updated information more frequently, users can more easily identify and monitor features and changes that occur within their service areas. Multispectral space imagery is "information rich," revealing such visual details as vegetation types, water bodies, buildings, and other man-made or naturally occurring features. These are important details when monitoring vegetation encroachments, construction of new facilities, and storm water run-off. A new generation of feature extraction products currently in development will provide a level of land information detail to utilities that has never before been available. This enhanced, digital information will allow users to perform automated change detection, land use classifications, and layer analysis more quickly and accurately than ever before.
• Compatible with AM/FM/GIS - Compatibility is no longer an issue when it comes to integrating raster-based space imagery with vector GIS environments. Today's space imagery products can be provided to users in most GIS-compatible formats, now that major GIS software vendors have integrated raster handling capabilities in their systems. Applications of Space Imagery in the Utilities Market
The use of space imagery in creating and maintaining a digital land base is becoming increasingly accepted by utility companies responsible for gas, electric, telecommunications and water-related services throughout the country. The following is a brief overview of several evolving applications that are now made possible with a temporal digital land base: Gas & Electric
In right-of-way management applications, gas and electric companies are using space imagery to identify potential service interruption problems before they occur without the need for frequent field inspections. For example, some electric companies are monitoring vegetation growth in right-of-way locations to identify dead or dying trees that could potentially damage power lines and cause power outages. By doing so, tree trimming operations can be conducted more efficiently by directing crews to potential trouble spots before any damage can occur. Gas companies can also use this new information technology to monitor pipeline locations for vegetation encroachment, identification of leaks, and conducting government required pipeline inspections. Further, gas and electric utilities can use this imagery to identify man-made encroachments such as roads and buildings that have been built on right-of-ways and could interfere with service.
For corridor/site planning applications, gas and electric companies could use high-resolution space imagery to identify optimum placement locations for facilities and infrastructure within a specific area. Planners can analyze the imagery to identify the best route to lay gas pipelines or install power line poles based on terrain and other land features which could impact both the performance and costs of their systems. By viewing imagery and utilizing associated geographic information right from the desktop, much of the analysis can be conducted from the office, thereby avoiding unnecessary and costly time in the field.
Another potentially valuable use of satellite imagery is in disaster management. Natural disasters such as earthquakes, floods, hurricanes and fires can take a heavy toll on a utility company's infrastructure. By comparing its land base prior to a disaster with space imagery of the same area immediately after a disaster has occurred, a utility company can identify trouble spots more efficiently and quickly and dispatch repair crews to those priority locations. This allows the utility company to get service back on-line faster and reduce costs by more efficiently dispersing their repair crews and other resources where they are needed most.
"State-of-the-art information technologies like high-resolution space imagery have the potential to enable utility companies to operate more efficiently, reduce operational and maintenance costs and remain competitive by providing enhanced customer services," said Donna Lindquist, senior research scientist, Pacific Gas & Electric Company. Telecommunications
The most common uses of space imagery in the telecommunications segment of the utility industry are in site planning and infrastructure management. Using a satellite-derived digital land base and digital terrain models, telecommunications system planners can more accurately determine the optimum locations for field facilities and infrastructure necessary to operate an efficient telecommunications network. Companies installing miles of fiber optic and coaxial cable can maximize service capabilities and reduce costs by using space imagery to identify the most efficient and least costly routes for infrastructure and network expansion.
For wireless communications network planning in both personal communications system (PCS) and cellular applications, high resolution space imagery has multiple potential uses including providing data for signal propagation studies, base station and cell site planning and location, site management necessary for the placement of wireless communications towers and microwave stations. This imagery is a valuable information tool for designers of PCS networks for determining exactly where to locate PCS-cells to maximize service coverage, especially in dense urban areas. Water
Potential uses for space imagery in water-related GIS applications include watershed management, run-off projections, environmental impact analysis studies, determining snow pack projections, and flood plain analysis, to name a few.
"There is a significant market for satellite imagery in the water resources field," said Robert Weir, deputy director of operations and maintenance for the Denver Water Department. "The only way we are now able to project run-off yield is from stream gauges and physical snow course measurements. The addition of snow patterns from year-to-year, using pattern change detection programs, would provide another valuable tool to water resource engineers as they attempt to accurately predict run-off."
The Metropolitan Water District of Southern California has used space imagery extensively in a variety of GIS applications related to water-use planning, forecasting and conservation. The company will potentially use high-resolution space imagery to identify large water users within its service area so that it can more effectively target water-use education programs to those users and help them apply water resources more efficiently.
"With higher resolution imagery, we can target our outdoor conservation program to a much broader base," said Scott Silva, a landscape program coordinator for Metropolitan. "We've been waiting for this type of refinement in imaging technology for quite a while." Information Products
High-resolution Earth imagery is currently available in Space Imaging EOSAT's digital archive from several different satellite and aerial sources The Indian Remote Sensing Satellite is already filling the CARTERRA archive with the world's highest resolution, commercially available space imagery: IRS-1C, which boasts a resolution of five meters.
Recognizing that space imagery alone may not be the only solution for some information requirements, Space Imaging EOSAT has recently formed an innovative alliance with 11 leading aerial services and mapping companies in the U.S. to offer users a broad array of high-resolution Earth information products. When aerial imagery from this Mapping Alliance Program (MAP) is combined with space imagery collected by Space Imaging EOSAT's own satellite and other existing satellites, a broad range of customer information requirements can be satisfied. In many cases, the solution isn't an "either/or" proposition when it comes to whether to use space or aerial imagery. Users can now access one or both imagery sources from a single provider.
"Aerial and space imagery are complementary technologies," said John Thorpe, chairman and chief technical officer, Analytical Surveys Inc. (ASI) of Colorado Springs, Colo. ASI is a partner in Space Imaging EOSAT's MAP program and is currently working with the company to provide imagery for a project within a large electric utility company. "One-meter resolution will be the dividing line between the two technologies once the CARTERRA 1 satellite is launched and generating imagery," he said. "For utility applications requiring sub-meter resolutions, aerial imagery will continue to be a practical choice. While both aerial and space imagery will be available for a range of resolution requirements, in many cases space imagery may be a more economical solution."
David Nale, president of ADR Inc., Pittsburgh, Penn., another partner in the MAP program, added, "Utility companies generally utilize imagery for two key applications - service territory management and facilities management. One-meter space imagery will be ideal for identifying the precise locations of facilities, street centerlines, generating stations and other service-related information. However, for facilities management and engineering design purposes and for monitoring pole inventories, transformers and street lights, for example, aerial imagery will continue to be the predominant information source." What's on the Horizon?
The evolution of space imagery and related advanced Earth information products is rapid and continuous. This December, Space Imaging EOSAT will launch its CARTERRA 1 satellite. This satellite will be the first source of the next generation of commercial space imagery - 1- meter panchromatic imagery, 4-meter multispectral imagery and 1-meter color enhanced imagery - which will be available to the global marketplace through Space Imaging EOSAT in early 1998 as part of its expanded CARTERRA product line.
Additional enhanced CARTERRA products are being developed that can be overlaid on a satellite-derived digital land base to provide enhanced information changes in land use/land cover, street centerline and related information, spatial attribute data such as business locations and demographic information, and other factors important to maintaining an accurate land base. Additionally, value-added services are available that can assist utility companies in maximizing the effective use of space imagery in such applications as site/corridor planning, facilities mapping, hazard/disaster management and right-of-way-management, and others. Conclusion
The increased availability of high-resolution space imagery and related Earth information products is allowing new utility applications to evolve from the technology, much the same way the industry found ways to effectively use GIS when it was introduced more than 25 years ago. Many industry insiders believe we have only scratched the surface when it comes to applying this new information technology. As improvements to the technology continue and industry acceptance grows, the digital land base and related Earth information products will become an invaluable asset to utility system planners.
"Accuracy is very important to a utility company when it comes to applying any type of imagery to GIS applications," said Duane M. Gilbert, an early advocate of using imagery in GIS applications and a 37-year veteran of Public Service Company of Colorado. "A utility service provider must be able to regularly verify its file information with what's actually occurring in the field, whether it be identifying the exact location of a particular home address or a power line or transformer within a new subdivision. The capabilities promised by today's space imagery technology may well provide a valuable tool for solving the age-old challenge of creating and maintaining accurate land information." About the Author:
Ron Elsis is the market segment manager at Space Imaging EOSAT. He may be reached at 303-254-2057.
Back
|
