I've always said that the skatepark should be designed around the site rather than designing the site for the park.

In short, a site holds the magic to the park and some really nice locations can be easily overlooked in the pursuit of a flat area.

• Is there a little elevation gain that can be incorporated into the park to create a unique obstacle?
  
• Is the park facing South to make best use of the sun? Is there a big shade tree that can be incorporated for summer shade?
• Is there a house or a neighbor that should be protected?
  
• Is the entrance situated so that kids entering the park don't get run over?
• Does the engineer understand the unique nature of a skatepark?
• Is there an area for parents to relax?
  

In most cases the site is looked at like a chalkboard on which designers draw a skatepark but the problem comes when the site isn't flat like the chalkboard the first reaction is to flatten it!!

Work with it!! Make the park fit the site... it isn't that hard but the rewards can save thousands of dollars in development and engineering costs.