Mountain Bike Bill, The Dirt on the Dirt

Historic San Diego Flume Trail

This past weekend, I did a “nearcation” at the Lake Jennings Campground in Lakeside. While enjoying the weekend I checked out the nearby Flume Trail. It is called the “Historic Flume Trail” in many sources the west end of it is referred to as the Helix Flume Trail. To further complicate matters there is another trail out of El Monte Park to west that is called the flume trail that only crosses over the actual Flume trail.

Sprocket surveying his “Kingdom” overlooking Lake Jennings

All of the naming up-bub aside, The Flume Trail follows along the route of the a 35-mile long wooden water flume that was completed in 1889 that brought water from Lake Cuyamaca in San Diego’s East County into the La Mesa area and beyond. The flume employed numerous cuts, several tunnels, and more than 300 wooden trestles wood to maintain a uniform fall of 4 feet, 8 inches to the mile. Two of the tunnels can be seen from along the segment of the trail we rode.

There are plenty of kiosks along the trail to provide some history of the route

The completion and filling of El Capitan Reservoir in the 1930s put an end to the flume’s usefulness, but it was plagued with issues well before that such as a trestle collapse in 1919 and just not enough water moving and evaporation. The nine million board-feet of lumber used for the flume itself and the trestles were scavenged a long time ago.

One of the ravine dips along the flume trail

If you are not staying at Lake Jennings campground like we were you will have to put in some work to get up to the flume. Wither you start at the Helix Water district end or the El Monte Park end you will have a relentless set of switchback to climb up to get the the Flume trail proper. 10-16% grade and around 400 feet of elevation to gain. Here is a route I did that involved using both the El Monte and Helix switchbacks. (I don’t recommend this route, use one or the other and do an out and back on the flume) Once up on the flume things are pretty flat except where there were trestles in those spots you will have to descend down and then back up the other side of the small ravines. There are a couple of spots that will be hike-a-bike for most folks, but they are very short.

One of the spots that most folks might do some hike-a-bike

Our effort started from the campground was easy with four miles and change from and camp out and the same back. We turned around at the Cape Horn Tunnel.

One of the Ravine Dips
Little bits like this are worth the price of admission

This section of the flume was not shown on Trailforks so I added it. This was my first time adding a trail to the site and the GPS track could use a little cleaning up but you can find it on there now. There are some other trails that need to be added as well.

El Monte Valley from along the Flume Trail

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