Vegetation Control of Transmission Lines Right-of-way

The vegetation occupies a considerable part of the domain limits of the powerlines in the region north of Brazil. Surveillance and monitoring of the right-of-ways in all the Brazilian transmission lines, regarding the clearing and cleaning, are periodically done through field inspection or by using a helicopter. In this context, the remote sensing is presented as efficient tool in the biophysics identification of areas of vegetal coverage and its characteristics - through techniques as indices of vegetation and classification of images - supplying subsidies to its diagnosis and monitoring. Once identified any irregularity, the TBE Company begins its plan for the next cleaning and clearing task. One of the Company´s line, located in the Northern part of Brazil (Amazon area), deserves special attention due to dense vegetation surrounding this line right-of-way. Information Systems containing geo-referenced data of the transmission assets, lands where the line passes, vegetation around the line and the applicatives utilized are useful tools to improve the efficiency of the maintenance engineering. Satellite images, aerophotogranometry, videography and airborne laser scanning are now available in the market. Due to the accuracy they offer (spatial resolution), these tools can well be applied to track not only invasions to the transmission line right-of-way but also to monitor the surrounding vegetation. In this paper is also presented an analysis of vegetation made for about 40 km of powerlines, using Quickbird image, considering the necessity of raised space resolution for coverage of the band - 100 m of edge of the line - as well as in the distance enters the vain ones of the towers, of 420 m on average. It obtained vegetation classification accuracy of 85,9% using Maxver classifier.