You need to take the water out of the jails or use some hint brushes or something so the jail water isn't drawn from the outside, or make the jail water level the same as the water in the map. r_speeds are tripling with reflective water enabled, which means the reflection is being drawn more than once.
You can probably take the steps out of the shore now, and you might want to get fancy and use the transition grass/dirt texture as well. The map is up on the beta server for testing.