N
either of us was in any hurry to get home, and after the last school bus pulled out of the lot, we stood looking through the fence at the edge of the concrete overpass that carried Royal Avenue across the drainage ditch bordering the school on the east. Looking down, we could see a trickle of water in the channel below us.

“It’s pretty,” I said.

“I like the way the sun reflects ripples there,” Charlie said, pointing to the concrete wall below the bridge.

“I wonder where the water is coming from,” I said. It had been several weeks since our last rain.

Watching for traffic, we crossed the street, and looked through the fence on the other side, trying to trace the source of the water. The channel angled off slightly to the southeast, and disappeared from our view behind the row of homes there.

I had never paid much attention to these vestiges of a network of dry washes that laced our valley floor. These arroyos had been part of the landscape here for centuries. It was easy to overlook the fact that the shallow ditch that ran behind my house was part of a vast watershed encompassing well over 300 square miles, but the main channel, the Arroyo Simi, was hard to miss. With its headwaters at the foot of the Santa Susana pass, the Arroyo Simi snakes through Simi Valley for more than 12 miles on its way to Moorpark, where it joins the Arroyo Las Posas. From there it continues to Camarillo, where it connects with the Calleguas Creek, eventually emptying into the Pacific Ocean at Mugu Lagoon. In the 1950s, the U.S. Army Corps of Engineers lined much of the Arroyo Simi with rock to minimize erosion. As homes were constructed, many of its smaller tributaries that meandered through the new tracts were shaped and compacted to improve the flow of water. Others, like the one below us, were lined with cement to impede the growth of weeds. These channels were an important component in the region’s flood control infrastructure.

As we continued east along Royal Avenue, the arroyo was hidden by homes, but we caught a glimpse of it at the end of the block where the channel crossed under Fourth Street. When we reached First Street, we turned south, and made our way into the tract of homes. After walking past two or three houses, we came to a chain-link fence and a gate where the same cement channel passed under the roadway. The afternoon sun shone warm on our backs as we stood looking through the fence, gazing down at the trickle of water that we had followed all the way from our school. The arroyo curved to the right and was lost to our view.

“Let’s see where it goes,” Charlie said, and handing me his books, he was up and over the fence in a matter of seconds. His agility surprised me. Complain as he might about P.E. classes, my friend was far more physically fit than me, and clearly more adventurous.

I handed our books over the top of the fence to him. I had never climbed a chain-link fence before. Taking hold of the pipe at the top, I tried to dig the tips of my shoes into the fence, but found the diamond-shaped openings too small. It seemed more like a gym class obstacle than an adventure.

“Just pull yourself up,” Charlie said as I continued to struggle.

I eventually made my way over the fence, taking care not to rip my pants on the sharp twisted wires along the top. I jumped to the ground, and checked my shoes for scuffs.

As we made our way leisurely along the wide shoulder of the arroyo, we could see houses on both sides, and realized that this channel was just over the back fences of these homes. If we had been there on a weekend, with families enjoying their back yards, we might have felt as though we were trespassing, but there wasn’t a soul in sight. The yards on both sides of the wash were empty and silent, giving the whole setting an otherworldly quality.

The contour of the channel walls changed a bit farther along the arroyo. The shoulder narrowed, and the steep walls gave way to sloped banks that angled down on each side. The trickle of water ran along the far edge of the channel, but most of the arroyo was dry and dusty. Without much thought to how we would climb back out again, we trotted down to the channel bottom, about 15 feet below. We continued in this way for a couple of blocks, not sure where we would emerge. Without streets or familiar landmarks to guide us, we couldn’t tell exactly where we were. A street overpass appeared just ahead, and we decided we had better climb out and get our bearings.

About 50 yards before we reached the street, we noticed an outlet in the right-hand face of the channel, a corrugated metal pipe about 4 feet in diameter. As we approached, I noticed water dripping slowly from the end of it.

As we came even with the pipe, we bent down to peer into it. The dark tube cut horizontally through the earth at an angle diagonal to the channel bed, but stooping down, we could see a faint glint of daylight at the far end.

“This must be the outlet from a storm drain,” Charlie said.

“That makes sense.”

“Let’s see what it looks like at the other end.” With that, he set his books down and climbed into the pipe. At times like this, Charlie’s adventurous spirit surprised me. I was even more surprised to find myself setting down my books, and climbing in after him.

At first I tried crawling forward, but the corrugated metal hurt my knees. The mud was a bigger concern, as I could see it caked on Charlie’s shoes as he crawled just ahead of me in the pipe, and I didn’t want to get my pants dirty. I rocked back onto both feet, crouching low in the pipe. I began inching along in a sort of duckwalk, my back bent over so my head would not brush the top of the corrugated metal. I kept my steps as wide apart as possible, trying to avoid the trickle of water flowing through the bottom of the tube. It was a slow and cumbersome way of moving.

After a couple of minutes, we emerged in a cement chamber about 10 feet wide and 4 feet high. At the top of the wall before us, we saw a rectangular opening at street level, about 6 inches tall and 4 feet wide. A metal bar bisected the opening horizontally. We immediately saw that there would be no way of getting out at that end.

“What a great hiding place!” I said.

“Yeah, but it’s creepy too,” Charlie said. “I sure wouldn’t want to be in here when it rains.”

“Me neither.”