There are a few major reasons the world is getting worse. The first and most important reason is over-population of the planet. Living in California probably makes this seem worse than it really is, but nevertheless I feel it is a big problem. Every person born is going to eventually need a place to live on their own, which means expansion of cities. I feel that any human expansion is equivalent to a negative effect on the environment.
Humans require water from other places, electricity, sewers, dumps, and many roads.
Just imagine what California looked like 150 years ago before the Gold Rush. The San Francisco Bay was larger and non-toxic, Hetch Hetchy Reservoir was a valley second in beauty only to Yosemite. Grizzly bears lived around Soquel. The Sierras could be seen from Mt. Hamilton clear as a bell. Lake Tahoe didn't have large, polluting towns surrounding its shores, Owens Valley would have been Owens Lake, Giant Sequoias wouldn't be dying from smog, and Desolation Valley would have been desolate.