Cenote Carwash

Kit up at a table, walk a few metres and giant stride off a wooden deck. Two ladders bring you out again, the car is parked within sight of the water, and for the first ten minutes you are in a garden rather than a cave. Five or six metres of water. Lily pads overhead, roots and branches standing in it, small fish working between the stems, freshwater turtles. Some days a small crocodile on the far side of the pool.

Then you swim west towards a fallen tree and the open water ends. Trunks and roots make a barrier across the cavern mouth, and behind it the space opens out into big rooms with chestnut coloured columns and walls stained close to black by tannin that came through here long ago. Daylight stays in sight the whole way. There is a thin layer of sediment on the floor and no reason to go near it, because the passage is wide enough to stay well above it.

One permanent line runs upstream from the entrance and that is the route almost everybody dives. It drops out of sight to about 15 m under shallow fallen trees. A downstream side exists and a few centres offer it. If Car Wash is the only cavern of your day, you will swim the same line twice.

The line ends at a stop sign, and that sign is the whole of the recreational dive. Turn round there and the best part of the morning happens facing the other way: trunks in silhouette against a bright opening, light coming down through the roots. The safety stop is spent back among the lily pads watching the fish. Forty to fifty minutes, and the shallow half is the half people describe afterwards.

For months at a time you cannot see into this pool from the deck. A green layer closes over the surface and the dive begins by dropping through it, two or three metres of opaque water and then clear. From inside the cavern looking out it tints the whole cenote, emerald on some days and yellow through orange on others, and divers who have been here in both states describe two different sites from the same platform.

What causes it is unsettled. One account is an algal bloom through the warm months. The other is tannic acid washing in off decomposing leaf fall after rain, which moves the pool within hours and answers to the weather instead of the calendar. The two explanations carry different seasons, no scientific work on this cenote exists to choose between them, and the only account that puts dates on the change is also the only one with nothing to sell. What is not in dispute is that the layer is shallow and the water beneath it is clear.

The cave behind the pond is its own system, which most of the famous cenotes within half an hour of here are not. Dos Ojos, The Pit and Nicte Ha are all entrances to Sac Actun. Sistema Carwash is surveyed separately: 3,232 m of passage, 26.5 m at its deepest, three cenotes linked together.1 Small, self contained, and better known than its size.

Which leaves the honest part. The cavern is short, has one line, and is where the cave courses on this coast do their line work, which is what has worn it. A stage cave diver with about a hundred dives across this cenote and Dos Ojos calls it beat up. One operator that sells the dive says as much itself, steering first time cenote divers to a cenote with more time underground and keeping Car Wash for photographers. That is worth trusting, because saying it costs the shop a booking. The reason to dive Car Wash is the garden, the shot looking back out and the fact that all of this started here. Book it for that and it delivers.

The taxi story is the one everybody tells, and it is only half right. The cenote is named for the Tulum taxi drivers who washed their cars in it, and they did. The published history of how the caves of this area were explored puts foreign campers here first, using the pool through the mid 1970s for washing their vehicles, diving, hacking around and bathing, with the taxi drivers arriving afterwards to have their cars washed there too.2

The same account holds the better story. In 1982 a group of open water divers from California, blown off the sea by wind, went for a swim in a pond beside the road and found an enormous opening in one side of it. They swam a few feet in, remembered what they had read about the caves of Florida, and got out. The next day they came back with two hundred and fifty feet of ski rope, and that was the first line ever laid in this cave.2 The US Deep Caving Team had dived the same pool shortly before and reported that there was no cave in it.

Exploration proper followed, and this pond is where it started. Car Wash came before Naharon, before Temple of Doom, before Mayan Blue and before Sac Actun.2 Credit it to a group. Jim Coke, Tom Young, Johanna DeGroot, Parker Turner and Mike Madden are the names that recur, and who went first is not settled. The survey that stands today came much later and from a different team, Phillips, Spangberg and Olsson, in September 2016.1

Which two cenotes you book decides what card you need, and Car Wash is not the one that sets it. Car Wash on its own is the entry grade of the regional cenote standard: an Open Water card, a non training dive in the last six months, minimum age 15, four divers to a guide.3 Sold with Angelita, two grades above it, the same morning is advertised as Advanced Open Water or 25 logged dives, because the harder cenote sets the requirement for both. Pairing Car Wash with Casa Cenote is the gentle version of the same day. Know which two you are being sold before you match your own card against them.

A guide is required unless you hold a full cave certification, and that rule belongs to the family whose gate you pay at. It is not a national one. Guides here need a licence from these owners specifically, on top of a full cave rating and a professional certification, which is why a shop cannot simply bring its own guide from Playa del Carmen.

Then the surface, which is the one thing worth asking about before you go. Rain changes it within hours in both directions, so what the pool looked like this week tells you more than what month it is. The green is not a fault to be planned around. Half the year it is not there at all, and the other half it is what a lot of people came for.

Money is 300 pesos at this gate, for this cenote, per diver, and a camera costs from 200 more depending on its size. Nothing here bundles, because this is a family gate and not a park: the next cenote you dive that morning collects its own money separately. Car Wash takes cards, which is unusual on this coast, but carry pesos anyway.

Last, expect company and dress for it. You are kitting up in a public swimming cenote with a café, lifeguards and a jumping platform, and cave students are on the line most days of the week. Leave the repellent and the sunscreen in the car, biodegradable included, and get into the wetsuit before you get out of it, because the mosquitoes are exactly why people reach for a bottle they are not allowed to open here. Snorkels, knives, gloves and surface markers do not go into the cavern.