The Parks Dept has posted the Draft Plan for Seattle's Citywide Skatepark Plan.  For West Seattle the following has been recommended by the Skatepark Advisory Board: 

 District size parks at the High Point Playfield and the West Seattle Stadium (although there is an additional note that the Stadium recommendation is not supported by Parks Staff, as it conflicts with a planned future golf driving range at the Stadium).  Skatespots are recommended at Hiawatha Playfield, Delridge Playfieled and Roxhill Park.  A Skatedot is recommended at Alki Beach.  Finally, the Advisory Board also recommends that the Myrtle Reservoir be added as a site for consideration. 

 To read the full 44 page document to learn about the features of each type of skatepark facility, please see: http://www.seattle.gov/parks/projects/Skatepark.htm