The fix isn't going to be easy. I'm not a hydrologist or a biologist,
but the root causes seem to be two things: water temperature, and pollution from
runoff/wastewater. Cooling the lake would require deepening the
lake, an expensive and lengthy proposition. It's probably worth doing; we
need to decide what we care about with our natural resources, and making Utah
Lake better is part of that. Cleaning up the pollution is a
challenge as well. Waste treatment facilities aren't really up to where
they should be, and it's very expensive to fix. We also have no real
regulation about runoff, which means that farms and lawns draining into the
lake take fertilizer with that runoff water, which feeds the cyanobacteria (and
puts strain on the fish). It's going to take money to fix, accompanied by
stricter regulation. I like a green lawn; I do the weed'n'feed like
everyone else. But if it's having an impact on the lake, we need to
consider how we deal with this.
If this is going to be a seasonal occurrence, I'm glad I never bought a
house down there.