In this monthly feature, we span the globe to examine Our Changing Landscape with time series of medium resolution RapidEye satellite imagery. The RapidEye archive dates back to late 2008 and already contains more than 7 billion square kilometers of data. This month, our recent trend of looking at dams under construction continues with one of the world’s most controversial sites, Barro Blanco Dam in Panama.
The RapidEye Constellation
RapidEye is a constellation of five 5-meter medium resolution satellites each offering five spectral bands of information. The RapidEye constellation offers daily revisits to every location on the planet with a huge footprint that is 77-km wide. The data is priced competitively with a starting cost of $1.28 per square kilometer for all five spectral bands – academics do receive discounts. RapidEye adds a fifth band, the red edge, to the ‘traditional’ multispectral set of blue, green, red and near-infrared (NIR). The additional spectral data in the red edge band allows users to extract more useful land ‘information’ than can be from traditional 4-band imagery sources. When RapidEye imagery is ordered as a Level 3A Orthorectified product, images from multiple dates are extremely well registered, making it the ideal data source for Our Changing Landscape.
Barro Blanco Dam, Panama
Unlike our stop last month in Turkey, there is an abundance of information on Barro Blanco Dam, likely given how controversial the project is. And as has been the trend in these articles, we are not here to make a judgement call; rather we are writing this article to show our readers how imagery can help them see changing landscapes over time. As such, the focus will be on the dam itself, we will leave it to our readers to dig deeper into the controversy if they prefer with some of the hyperlinks provided here.
With that said, Barro Blanco is a gravity dam whereby water is held back by the weight of the stone or concrete in the structure so that each section is supported independent of its neighbor. The dam is planned to be a bit over 147 feet when completed with the ability to hold back a maximum surface of about 1 square mile (sq mi), of which 73% would be newly inundated lands. Barro Blanco is located in rural south-western Panama along the meandering Tabasara River. The dam is about 11 miles from the Pacific Ocean and about 50 miles from the Atlantic. When completed, the dam is expected to deliver 28.8 Megawatts of hydroelectric power.
The root of the controversy surrounding Barro Blanco Dam appears to be the flooding of the semi-autonomous lands around the new structure that belong to the native Ngöbe and Buglé indigenous people. The dam will flood the ancestral homes and fertile lands of about 5,000 residents of the region. Barro Blanco was planned for completion in 2015 but multiple delays caused by local and international protests as well as non-compliance with Panamanian environmental regulations have pushed this date back. As of February 2015, the project had been halted by the government, pending the outcome of a widely publicized court case. While there is a plethora of information about Barro Blanco Dam on the internet, here are a few of the sites we found most interesting before we move on to the 5-meter RapidEye images that chronical the site from 2009 to 2015:
- A chronology of the dam current to mid-2013 put together by International Rivers.
- A detailed thesis written by Katharine Evans of Wesleyan University.
- A multi-part story published by the Pulitzer Center on Crisis Reporting.
If you would like to find out more about using RapidEye for your academic studies, engineering projects or any landscape analysis, let us know at [email protected] or (303) 993-3863.