The SV Dam is a playable location in Skate 2.
In the career mode (This location is clear in the Free skate mode.) this location is unlocked by completing the final Thrasher challenge "The Scene of the Crime." This is in reference to what got you in jail in the first place, attempting to perform (or drain) a trick on the dam.
The SV Dam is comprised of 3 sections. The Murderhorn, the Edge, and the actual dam.
The Murderhorn is a spawn point you unlock from doing Danny Way bonus challenges. It spawns you on top of one of the pillars above the dam. It provides a massive gap into the ramps that lead into actual dam.
The Edge is the road and sidewalk below the Murderhorn. It's the primary passage to the massive ramps that lead into the dam.
The Dam is the main part of this location. It contains ramps and massive hubbas. You'll likely have massive speed while you're down here so try to land everything perfectly. It contains a secret grass path to the Top of the E, another Danny Way spawn point. The Dam will eventually lead to the new spillway.