I don't know of any spots specifically close to UP, but here are the spots we ride around here.
Tron in Beaverton on 158th between Hwy 26 and Walker Road.
Reedville off Cornelius Pass Road in Hillsboro.
Tigard by the police station on Hall in Tigard.
Chehalem Skate Park in Newberg at the end of Blaine Street on East side of town.
Tualatin has a small skate park near the police station.
Glenhaven skate park off 82nd in NE Portland is...not the safest place.
Ed Benedict park in NE Portland off Powell East of I205 is a street-oriented park.
Pier Park in NW Portrland has some big bowls and a full pipe, but it's also not the safest park.
Holly Farm is a really small park close to I5 and Capitol Hwy in SW Portland/Tigard.
There are also parks in Vancouver, Battle Ground, West Linn, Milwaukie, Woodburn, Sandy, Estacada, Hood River, Woodland, Centralia, and there's Windells up by Mt. Hood.