Truthfully, we weren't too impressed with this hike, but that might have had to do with the circumstances of the day.  It was hot with no clouds in sight, and virtually no shade, except for a couple of small groves of oak trees.  We had our dog Flora with us and she was wanting to stop to rest at every small shady spot she could find.  The trail was a fire road and the little rocks in the dirt wore down the pads of Flora's paws.  A little past halfway, she started having trouble.  I carried her for short distances - she weighs 40 lbs, so I couldn't do it all the way.  Luckily we had some moleskin and vet wrap bandage in our backpacks, so my wife was able to wrap Flora's paws, and that helped her make it almost to the car, and then I could carry her the rest of the way.The trail is part of the North Watershed of the East Bay Trails of the East Bay Municipal Utility District (EBMUD). You'll need a permit to hike here, but you can get one online, and it is good for all the EBMUD trails (East Bay North and South Watersheds and the Mokelumne Area of the Sierra Foothills).  The trail we hiked was called Oursan trail and was the only one that allowed dogs on it.  It followed the west side of the Reservoir and then headed up into the hills a little bit, which did offer some nice views.  Parts of it were not well marked, so we had to back track once (if you see a sign that says "DUMP", you've gone too far and missed a turn).  Maybe the other trails in the district are nicer and have more shade, but I can't say for sure.

Better not to hike this one in the summer, but if you do, be sure to use sun screen/protection.Restrooms at the staging area.Dogs only allowed on Oursan Trail.It's a Utility District, so parts of it look like a construction site and there are lots of power lines around.