It was small, plastic and yellow, gamely navigating through the rocks and bushes along a stretch of the LA River called the “Glendale Narrows” on the coldest day of the year.

My family and I were on a tour sponsored by Friends of the L.A. River that started at the Sepulveda Basin in the Valley where 12 streams and tributaries converge and wildfowl such as turkey buzzards, kites, egrets and blue herons abound. The tour concluded five hours later along a concrete, glass-strewn stretch in industrial Maywood. (The L.A. River runs 52 miles to the Long Beach Harbor, but tour organizers left the lower half for another trip).

Lunch was on the concrete banks in scenic Atwater, and that’s where kayaker George Wolfe hauled his craft up the embankment to say hello. He’d like to kayak the river’s entire length later this year and was on a reconnaissance trip. More rain would raise water levels and make his pilgrimage easier, but some overland hauling might be unavoidable.

As a novelist whose books are set in L.A., I’m always searching for new ways to imagine this place, and Wolfe’s quixotic quest enchanted me. It’s a reminder of the magic that can be conjured here, often where one least expects it. There is grace in small, unbidden moments, beauty hidden amidst chain link, trash and concrete. One wants to genuflect amidst the sycamores and native grasses along the banks (planted by Northeast Trees) and give whispered thanks.

Blues singer Robert Johnson talked about meeting the devil at a crossroads, but the crossroads where our tour stopped yesterday sent a different kind of shiver up my spine. It was a concrete ditch in Cypress Park, where the fabled Arroyo Seco of Pasadena (which wasn’t so seco Saturday) empties into the LA River.

In 1769, Spanish explorer Gaspar de Portola stopped on these earthen banks, and marveled at the cottonwoods and alders, the wild roses, the natural paradise he’d found. Nearby, in 1781, the Spanish would establish the pueblo that became Los Angeles.

Two-hundred and thirty-eight years after Portola, I pick my way past broken glass, rusted metal pipes, rotting lumber, fast-food containers. What his expedition saw is long gone and I stand in sludge at the crossroads of an industrial nightmare. Overhead, half a dozen bridges, overpasses, railway trestles and freeways weave and cross. Metal clangs, cars roar. Colorful graffiti covers most surfaces. Filthy bedding is wadded under one embankment.

But the chill I feel has nothing to do with this or the weather. It comes from the Indians I hear, creeping through the hills to meet Portola. The calls of his men as they set up camp, the bray and whinny of his pack animals. The exclamations of Father Juan Crespi, marveling at what they’ve found. Their voices whisper in the icy wind. They screech and groan each time a car shoots across overhead. They are the spirits of this place.

We hike along the trickle to where the Arroyo Seco ends. The water level is so low we can pick our way to into the middle of the LA River. My tennies squeak. My socks get damp.

My children run heedless, splashing and crowing with delight. They’re 8 and 10 and they don’t see the smog-choked weeds, trash and squalor. Like Portola, they see a new world to explore. They skip rocks. They send boats of dried leaves floating down to Long Beach. Inexplicably, they find a fresh orange and lob it as far as they can. Then they hop and leap and shimmy over to the concrete islands in the middle of the L.A. River, where they plant the flag of childhood.

I think about how each generation has the capacity to create the world anew. Maybe by the time they’re grown, there will be trees and a riverwalk here. That’s what FOLAR envisions and is working toward. Not Portola’s paradise, but not this abomination either.

“This is uncharted territory, and I claim it,” my 10-year-old shouts out jubilantly. “I’m the first human ever to set foot on it.”

I smile and tell him, “Indeed you are.”