Thousands of environmental activists marched through the streets of Santiago Chile Wednesday (April 11) before the protest descended into chaos as police fired water cannons at the crowd.<br/> <br />The activists were protesting a Supreme Court decision giving the green light to the controversial mega dam HidroAysen.<br/> <br />The activists blocked downtown traffic and riot police rolled out water tanks to disperse the crowd.<br/> <br />Protesters set tyres on fire to block streets before police used the water tanks to put out the flames.<br/> <br />The $3.5 billion project is a private venture between two of Chile's largest energy companies.<br/> <br />Environmental studies conducted have indicated that the project would have a major impact on the environment.
