This drain is also identified as "Megadeth" by the graffiti across the top of the concrete inlet. It is well barred at both ends, so would require some bar modification at each end prior to entering. Other hazards include the constant flow of water from a small stream, the downward slope of the drain, and the small size (3 ft or 1 meter diameter corrugated pipe). There are several alternative entrances to the drain, including a short 18 inch(!) side pipe and three manholes (each in the middle of a street). The entire drain is 1190 ft long (about 400 meters), with the last 145 feet being 36" RCP. I have a fairly detailed map of this drain from the city planning office, and it looks fairly unexciting. I suppose the only good use for this drain would be charging tourists $10 a head to slide down it into the ocean in the summer.

Pictures are on the way
Perhaps I should buy one of these to check out questionable drains
 
 
 

According to a 1983 map I acquired, this drain replaces a 54"x36" drain which ran under the landfill to a larger stream. This older drain runs at right angles to the current drain, and the only information on the map is that it was supposed to be shortened by 40 feet and capped off. This means that it is probably dry, but the other end is likely buried beneath the landfill. I have been unable to locate the original inlet, and the only manhole I can find on the map appears to be in the landfill as well. For all practical purposes, this drain exists in a state of limbo, a closed underground chamber with no entrance and no exit.
Also, I have no idea if the dimensions given are for 54" high by 36" wide, or the other way around.