Above Ellensburg, heading west, take hgy 10, pick your spot. Some high bank, to very high bank, some close to the road. Note to self, step gently in wading boots on the very dry grass.
Some nice access south of eburg, towards Yakima. Take the road along the river, not the main highway, stick close to the river in the lower canyon.
You may still subject to the bikini hatch.