Finishing the Drop Off Tunnel
I hadn't been back to this tunnel in years, but it always nagged at me that I never finished going as far upstream as possible.  Well, Phil hadn't been in this system at all, so there was the excuse I needed for a return trip.

Here's Phil near the entrance I exited from once, entered from last time I came back, and where we entered again this time.

Artwork by Soler (who dated the work 1986.  Yeah, right.  More like 2006).

First thing Phil and I did was head upstream and continue the journey...

Metal bits always collect in shallow pits like this one...

Here's what we found in it: an industrial blade, padlock, drain cover, and lots more junk.

A curbside drain up above us, but too high to reach and stick the GPS out of.

A relatively small side tunnel.  Phil checked it out, but it just seemed to go on forever, so we stuck to the main tunnel and continued upstream.

It kept getting smaller up ahead.  Beyond this point it stepped up several inches.  Phil went ahead and scouted it while I got a GPS reading from a curbside drain accessible through a nearby side tunnel.  Unfortunately, he left his camera where we parted ways, so he could move faster.  As a result, we didn't get any pictures of the very end, but it wasn't very much farther than I left off last time.  Total distance from the outfall at the river (estimated from connect-the-dots sums between multiple GPS readings): a little under six miles.

Next we reversed course and headed downstream since Phil had never been in this system at all before.

You know what else was heading downstream?  Some sewage.  This is a bit running into the main tunnel.  The white stuff is dissolved toilet paper.

This is where it was leaking from, that joint in the foreground.  There's no frame of reference, but this pipe is under 18" in diameter, so it wasn't a lot, fortunately.  However, overall this system has more leaks in it than any other I've encountered.

This is a leak of a different kind: Pure water.  It isn't clear here (and I didn't want to risk getting the camera wet attempting a profile shot), but water is gurgling up through a crack in the bottom of the tunnel.  I run across this periodically (as you might have seen elsewhere on the site), but I still don't know if it's groundwater or from a leaking water main.

All tunnels have shovels.  I would put money on this.

Phil spotted a small side tunnel I hadn't noticed previously that opened out into this moderately-sized section.  It was warmer in here than in the main tunnel, so the lens fogged over.

Little roots were growing though (or from?) the ceiling here.

Continue to Part II