By DENNIS WYATT 209 Living The coolest spot to see spring moseying toward summer in the Manteca-Ripon area can be found along the Stanislaus River in one of the few remaining stands of riparian woodland in the Central Valley. Not only does the thick canopy of oaks drop the temperature by 10 degrees by the time summer rolls around but when the evening Delta breezes kick in Caswell Memorial State Park becomes even cooler. And if you're looking for a good old-fashioned dip in a river with very clear water, Caswell has two popular beaches — Willow Beach and Salmon Bend Camp Beach.