Lake Del Valle is a 4 plus mile long narrow fresh water reservoir. There's a well maintained 2-pier boat launch, but you could launch from anywhere along bank except the marina and swim areas.
The summer water temperature is pool-like. There's a 10mph motor boat speed limit. Dogs are allowed anywhere on/near the lake. From the boat launch you can head north and cover 2/3 of the length of the lake to the dam or go south for the remaining 1/3 of the lake. Summer winds are consistently northerly and kick up around 11 to subside around 4. Even with high winds, the water remains fairly calm and never more than 1/2 of the biggest boat wakes. There is no discernible current. The water quality is (3 foot visibility) remarkable considering the popularity and size of the lake. Most lake goers stay near the swimming areas. There's one near the marina and one in the southern tip of the lake. There are numerous beaches and coves. There's a 15 foot long rope swing tied off an overhanging California live oak in the northernmost cove near the dam.
It takes me about 4-5 hours of consistent but comfortable paddling to get my tandem loaded with two kids from the dock to the dam, an hour for lunch, and back. Fast single paddlers can do the round trip without breaks in about 2 hours.
The deer and other wild life come out around sunset to the waters edge to forage and drink. The hills are the familiar golden brown typical of northern California in the summer and lush green in a wet winter. Not sure what fish are stocked in the lake, but fishing is allowed with a CA permit of course.
boat launch, kayak/motor/pontoon boat rentals, bathrooms, camp sites, picnic areas, public swim areas, dog friendly.
Invasive mussel inspection permits and fee at entrance.
California fishing permit regulations apply.
From Fremont, CA:
take 680 N., exit 84 towards Livermore, right on Vallecitos Rd., right on Concannon Rd., right on Tesla Rd., right on Mines Rd., Right on Del Valle Rd.
Del Valle Regional Park Website: