It's maybe 30 miles north of Sacramento. Take I-5 North from Sacramento
then 99/70 Yuba City/ Marysville north.
You will get off of Hwy 99/70 towards
Yuba City on Hwy 99.
Follow that north, after crossing the Feather river you will
see a turnoff for the Garden Highway
towards the right. There will be a fruitstand on the right corner along
with a nut drying facility.
Follow that road north past Messick Rd and on the right you will see
a boatlaunch sign where the drive to the ramp turns off to the right.
If you miss the Garden Highway and see Messick Rd on the right, Turn there to end of road where it hits Garden Highway then left and a right.