The eastern portions of Washington State are mostly desert with as little as 5 inches of rain annually. This probably comes as a surprise to people accustomed to thinking of Washington as "The Evergreen State"; however about 1/2 of the state is anything but green. Brown would be more like it.
Vantage has its own beauty however. Basalt cliffs laid down over tens of thousands of years by active volcanoes rise vertically out of the water and soar from the 800 foot "pool elevation" to over 4,000 feet and, to the west, even higher. Trees - except for the petrified Gingko variety - won't interfere with your view. But that can be an advantage since a lot of the local critters get on with their lives in full view of the paddlers who float by.
Launch at the big parking lot/launch ramp next to the freeway or visit Greg and Sue at the former A&W restaurant (you will recognize it, trust me) have a burger and shake and ask them for permission to launch at their beach or docks at the tiny Vantage marina.
The current runs to the south at about 1mph so if you paddle north first you will have a bit of help coming back. And you'll go right past the old Seattle/Spokane highway (US10) where it plunges into the water. Look east and you'll see it climb out again. I've traveled that road (as a kid with my parents) and gone over the old bridge.
Further north is a lagoon on the western shore with the famous "Gorge at George" music venue high on the hills across the river. You can hear the bass lines and the applause but that's about it. Camping is possible on the sandy shores of the lagoon.
South of Vantage you paddle east to get around the freeway approaches to the new bridge and then along green wetlands full of birds and wildlife. About 7 miles further south is Wanapum State Park where you can camp if you wish.
Stay away from the eastern shore unless you are absolutely certain there will be no wind. The wind in this area almost invariably blows down from the mountains and can trap you on the eastern shore for days. Also watch out for changing water levels caused by releases from the numerous dams upstream of the Vantage area.
Two dams downstream (Wanapum and Priest Rapids - you'll have to portage) is the last free-running stretch of the Columbia River above the tidal reaches: the Hanford Reach. Bound on both sides by the nuclear reservation, there are people here who will cheerfully shoot you for landing. But you can float past in peace.
Vantage is best enjoyed in the fall when the weather in Seattle and Portland has turned cool and rainy but the weather in Vantage is still sunny and comfy. Better yet, the jet skiers and Board Boats have mostly gone home and you can paddle in relative peace.