Wow. This run was amazing. I call this a "secret" run not because it's hidden but because so few people seem to know about it. I've lived in the Bay Area for about 15 years now and I have never been on this trail, and I can honestly say that this is a tragedy. We ran for 13 miles and we saw 3 other people total. That's right. 3 other people. The rest of the time it felt like we were far away from civilization, in the Sierras instead of 10 miles from downtown Richmond. The Briones Reservoir Loop starts at the EBMUD Bear Creek Staging Area, just across from the EBRPD Bear Creek Entrance to Briones Regional Park. Confusing? Only until you remember that you want to run around the water and that will re-orient you.
A couple of important notes for this run. You need a permit. You can get one online or you can buy one in person from the EBRPD kiosk across the street from the Bear Creek Staging Area. Day use permits are $2.50, year long permits $10.
I would not recommend skipping this option however-- in the time that it took for me to get out of the car and use the port-a-potty, an EBRPD police officer drove up to check our permit. You also need to sign in as you leave the parking lot, and given the paucity of hikers or runners, this is probably a good idea. No doggies on this run, either. Apparently there are areas of the Oursan trail where dogs are permitted but they cannot go around the whole reservoir. This is also a great run for late spring or early fall (before the rains)-- much of this trail is exposed which might be ideal in the summer if you are training for Badwater, but for the rest of the mortals in the Bay Area, there are better summer trail options. The ruts left in the road from dried mud suggest that this area might be extremely muddy post-rain.
However, we hit the jackpot with the weather this morning. It was sunny and clear but cool enough that we enjoyed the sun as we started off on the Bear Creek Trail (go to the left as you get on the trail). This trail climbed up and down (never very steeply), showing glimpses of the reservoir through the trees. After crossing the reservoir, Oursan trail led away from the reservoir and up to El Sobrante Ridge, affording some absolutely stunning views. At one point we could see Mt. Tamalpais on one side and Mt. Diablo on the other...and green hills spread out all around us. Then the trail winds down to the edge of the reservoir, where it gently rolls through grassy fields and large oak trees before winding back to the parking lot.
It doesn't get much better than this run. Enough climbing convinced me we weren't wimps, but we could run the entire trail (no uphill Cataract trail, in other words!). Views of the reservoir and of surrounding vistas kept us continually surprised this trail is not more popular with the Bay Area. Bear Creek Road is one of the most popular bicycling routes for the roadies-- trail runners should take advantage of this little-known treasure.