From the Allens to today, Buffalo Bayou has helped define the city of Houston. Now, after decades of abuse, it may finally be making a comeback as an urban resource. If, that is, we don't blow our chance.

"Welcome back to the city," I thought. Waiting for my ride, I thought back to the bayou, where I had drifted with a pair of wood ducks, the male easily identifiable by his shaggy head. When I floated past a dead tree, I spotted a downy woodpecker at the top. His bill was half open as though he had something in it. Then I heard a high pitched scree, scree, scree, the sound of its young calling for food.

I wished Army Emmott could have been there with me. I wished life were simpler and the water in the bayou was as clear as it had been in his day. But that, I assumed, would never be. I couldn't imagine scooping a hollow out in the bayou's sand banks and drinking spring water. I couldn't imagine seeing bass in schools at the bottom of deep pools in Buffalo Bayou.

But following my trip I had a long talk with Janet Wagner, a landscape architect who's researched the history of the bayou for the flood control district's new erosion study. Wagner knows where the bayou was mined for clay, and knows the names of the brick companies that mined it and in which buildings you can still see the bayou-bred brick. She knows where the fords used by the Indians were situated on rocky bottoms and can show you how the early Anglo settlers damaged them by cutting deep ramps in the banks for their wagons.

When I wondered aloud to her if the bayou's water could ever be as clear again as it was in Army Emmott's day, she surprised me. Oh yes, she said. Buffalo Bayou is still fed by clear springs. And if we could control Houston's urban and suburban erosion and discharges, the bayou would carry the sediment that now discolors it out to the bay, and the water would again run crystal clear over its hard, blue-clay bottom.

We could have it back. We could have it all back if each of us took care of our own piece of the problem. If we kept our grass clippings and our soap suds and automobile oil out of the gutter. If we cleaned up our construction sites and our gas stations. It would take an effort, but I'd already seen how far we'd already come. And I knew now it wasn't impossible. If we took care of the moment -- the only time in which any of us ever had a chance to really make a difference -- Houston could have its bayou back.