Since this claim has been around for a couple of years now, there are several people who have provided competing theories for what this image shows.
This one includes the original image straight from the ESA rather than the one that was post-processed, colourised, rotated, recompressed and wrapped around a sphere in Google Earth.
This photo shows quite clearly that it is not a colony or a building of any sort and is the result of individual pixels being set to white. I don't know of a plausible explanation in which buildings on Mars could produce this image.
The page also provides a possible explanation for the white pixels (a data transmission glitch) and replicates the process on an aerial image of an area near the Grand Canyon by manually adding white pixels and post-processing the image the way it would be before appearing in Google Earth.
The end result looks like this:
Quite similar to the alleged Bio Station Alpha image.
Later still he shows another photo of the same area without any data glitch or buildings.
Another article on Fox News debunking an earlier article on the same site contains this explanation:
"It looks like a linear streak artifact produced by a cosmic ray," said Alfred McEwen, a planetary geologist at the Lunar and Planetary Lab at the University of Arizona and the director of the Planetary Imaging Research Laboratory. McEwen is the principal investigator of the High Resolution Imaging Science Experiment (HiRISE), a powerful telescope currently orbiting Mars.
Cosmic rays are extremely energetic particles emitted by the sun and other stars. For the most part, the Earth's protective magnetosphere blocks them from hitting the planet's surface, McEwen explained.
"But with space images that are taken outside our magnetosphere, such as those taken by orbiting telescopes, it's very common to see these cosmic ray hits. You see them on optical images and a lot of the infrared images too," he told Life's Little Mysteries.
As a cosmic ray passes through a camera's image sensor, it deposits a large amount of its electric charge in the pixels that it penetrates. If the particle passes through at a shallow angle to the plane of the camera, it affects several pixels along its path. The result is a bright streak on the image.
The digital compression software that converts the image into a JPEG file then "sort of smears out the image, giving it that pixelated look," McEwen said. What started as a clear streak in high-resolution turns into a streak that, in the armchair astronaut's words, looks like it is "made up of cylinders."
No matter which of the data transmission glitch or the linear streak artifact theories are correct, it is not a Mars colony.