"What was that?" I asked as the needle-nosed long-tail boat shuddered.
"I dunno," my friend Lane said with a shrug. "Maybe we hit something."
I turned to ask our boat pilot, but he was no longer manning the motor. He was flat on the deck, covering his head with his hands, trembling. This did not bode well for our floating-market tour in Bangkok.
"Excuse me, sir," I said, "but why are you ..."
Something slammed into the port side just above the water line, nearly toppling me overboard. What in blazes was going on? I peered over the edge of our 30-foot craft, expecting to see water gushing into the hull, but all looked normal. I motioned to Lane at the front of the boat, and as he lumbered down a deck no more than 4 feet wide, steadying himself with poles supporting a frilly canvas roof, something appeared to whir by his head.
"OK," I said to our guide, whose name escapes me 20 years later. "What is happening, and why are you lying on the deck?"
"Songkran," he said slowly, as if to a child. "Worst day for floating-market tour. I tell you, today no good!"
Lane scratched his head. "Yeah, come to think of it, he did seem a mite put off when we showed up."
It had seemed unusual that we were the only tourists to show up for such a popular attraction. But we still didn't know what had rocked the boat and why our guide looked petrified.
"Why," I asked, "is today the worst for ..."
Splat! Splat! Splat!
A fusillade of water balloons struck Lane and me simultaneously. Cheers erupted from both sides of the river. We hit the deck beside the guide as balloons exploded around us. I frantically dug into my backpack for a guidebook.
"Songkran, did you say?" I asked as I riffled through the pages.
I read aloud. Songkran, the book said, is the three-day Thai New Year celebration that starts April 13. It's also known as the Water Festival because people believe water will wash away bad luck.
I kept reading: Songkran means "move" or "change place" because it's the day the sun changes position in the zodiac.
"I think we want the part about water balloons," Lane said.
I hurried on: Family members pay their respects to elders by pouring scented water onto relatives' hands and presenting gifts.
"Does it mention anything about maiming tourists? I think that's the section we're looking for," Lane said as a balloon whizzed overhead.
"Oh, here we go," I said. According to the book, Thais joyously splash water on one another. When venturing into the streets, visitors are advised to wear goggles.
"What about venturing down the Chao Phraya River?" Lane asked.
"Doesn't mention that," I said. "Assume it's best not to."
"So what do we do?" Lane said.
"We go back!" our guide said. "Good idea go back now."
A dozen balloons pasted the boat.
"I don't know about you," Lane said, "but I paid for the floating-market tour, and I aim to get my money's worth."
We veered for shore, where delirious revelers armed with buckets and hoses were jumping up and down.
The guide gave the engine some gas, and we zoomed past just in time. Unfortunately, our retreat from the right side of the narrow canal put us within range of hordes on the left.
"Incoming!" Lane cried, and another barrage smacked the flimsy craft.
We swerved away and held a steady course down the middle of the murky brown channel. I peeked over the prow and groaned. Ahead of us, the canal narrowed even more. Hundreds of Thais lined up on both banks as far as we could see.
Then there were the bridges. Racing across each one were boys lugging what looked like trash cans brimming with water.
Down at my feet were wide, loose floorboards. I picked one up, faced the right side of the river and held it up like a shield. Lane snatched another board, stood behind me and faced the left bank. With the canvas top over our heads, we could ward off every weapon launched at us.
"Ha-ha, try and hit me now!" I shouted to our assailants in my best Peter O'Toole impression. "OK," I said to the guide, "run the gantlet!"
Our guide and the engine howled, the front of the boat rose half a foot, and we soared into the maelstrom.
Ninety minutes later, we limped back to the pier. Our boat listed severely to one side, the roof was in tatters from a direct hit and we looked as though we had spent a week in a convertible during monsoon season. It was one of the most humbling, disgraceful, thrilling and exhilarating experiences of my life. Even the guide managed a weak smile as we thanked him and tipped generously.
Lane and I staggered into the first cafe we saw and slumped into the chairs, ignoring the stares from the other patrons. A uniformed waitress greeted us and politely took orders.
"Would you like anything to drink with that, sir?"
Not thinking, I said, "Water, please."
"Me too," Lane said.
"Certainly," she said. She filled two glasses from a pitcher, poured them over our heads and ran shrieking into the kitchen.
After lunch, Lane and I bought ponchos and water pistols, then waded into the madness. Revenge was sweet.
After two decades, John Wood has dried off and is writing travel stories from Los Angeles.