Thursday, May 7, 2009

A Look Into the Validity of The 17th Water Ball Claim


If you didn't know this, TPC Sawgrass claims that they pull out nearly 120,000 golf balls out of the water surrounding the 17th hole each year. If you think that number is staggering, you're not alone. One of our readers, John, who admitted to having too much time on his hands at work, actually broke down the number (he even used Excel!) and came up with this staggering explanation of how that number cannot be possible. Here is the e-mail. I hope you enjoy it as much as I did.

Have you seen the postcard on Waggle Room from Sawgrass (Ed. note -- story about all the balls is here)? The one that claims that 120,000 (that’s one hundred and twenty THOUSAND balls a year are lost to the water at 17?

I saw that and instantly said “there is no goddamn way that’s true.” Then I set out to PROVE that there’s no goddamn way it’s true.

To prove this, let’s do some neato-nifty Fermi math.

Now, let’s start off with some theoretical assumptions to maximize the number of balls that can possibly be whacked into the water on 17. First, we will assume that it never rains. In Florida this is admittedly extraordinarily unlikely, but that’s math for you. Secondly, we will assume that every professional golfer on earth is stricken with swine flu and thus there is no Players’ Championship in our rain-free year, so that we can thirdly assume the course is constantly in use by the maximum number of players at all possible times. Setting aside for the moment the possibility of people playing glow golf – which, while fun, I do not recommend in a state with alligators – the question of what constitutes people playing at all possible times becomes one of daylight.

So how much daylight are we talking about?

The TPC at Sawgrass is just past 30 degrees north Latitude.

The good folks at Microsoft provide us with a very useful “Hours of Daylight by latitude” table.


A little Excel magic tells us that Ponte Vedra Beach gets, at a rough estimate, approximately 4,467 hours of daylight a year.

Going off the claim from the TPC that 120,000 golf balls go into the drink per year, we can calculate that for that number of balls to go in the water, 27 people per hour need to tee off at 17 and put their shot right into the drink. That’s once every 2.23 minutes.

So, under optimal conditions, for this postcard to be accurate someone has to put a ball in the water at 17 every 133 seconds for an entire year.

Given that our optimal conditions are completely, ridiculously, hilariously impossible, my conclusion is:

Damn you and your lying-ass postcards, TPC at Sawgrass.


First, I will admit that this is the most entertaining (and probably intelligent) e-mail I have ever received in all my years of blogging. I have a rule in movies that if I laugh out loud four times or more, I will consider it a success, and this e-mail did just that.

The only thing I will say is that I've heard of people going to Sawgrass and not even being able to get to the 17th because so many people are dropping golf balls and hitting them into the drink. It is like the grass behind the "Sergio Tree" at Medinah. Everyone wants a chance to do what the pros do.

Nonetheless, I hope you were as entertained as I was with this little fact-hunting exhibition. TPC Sawgrass, we need some FACTS!

Ball hunting photo courtesy of Caryn Levy, PGA Tour/Getty Images

9 comments:

Shank said...

That was very well done.

I think you're right though...it's the "G'head Jimbo hit another one." effect that could give TPC plausible deniability that the number is still accurate.

Stephanie said...

Yes, great job by John, but he made it a little more complicated than necessary :)
http://weiunderpar.com/104889358

And, Shane, it's not fair that you get emails like that while I get emails like...well you know.

One-Eyed Golfer said...

Our group was on the 17th tee about for only 7-8 minutes and donated at least a dozen.

120,000 might be a low estimate...

Adam said...

I've played the course four times and have never hit a ball in the water. In Feb of this year, I made a birdie (stuck it to 1 feet) and then par the next day. I played badly the other 17 holes, but 17 is the only one I remember. That's golf for ya.

John said...

Wow, I'm glad to see folks were amused by my little math exercise. A couple people here (and other places, which I never expected to happen) have raised a point, so let me clarify something:

The "a ball in the drink every 133 seconds" number is the absolute SLOWEST rate at which balls would have to be hit into the water to get to 120,000 a year. That's under "optimal" conditions which, as I point out, cannot possibly exist.

When you factor in things like rain, the Players Championship, slow days on the golf course (I'm fairly certain there aren't a ton of guys out there on, say, Thanksgiving), times it might be closed outright, the fact that no golf course on earth can start a foursome every eight minutes nonstop for an entire year, and the - GASP! - possibility that some people might actually keep their ball ON the green, the actual rate at which people would have to hit balls into the water to get to 120K a year is substantially faster. REMARKABLY substantially faster. If I had to make a wild first-order approximation I'd guess that the actual rate, when people are on the golf course, is something more like once every 30 seconds or so.

The key factor in all this is how many people per year actually get on the Stadium course, and when one considers that rounds there start at $200 and shoot up to 4 bills and more on the weekend, I have a hard time imagining it's enough to get up to the kind of numbers required for the TPC's claims to be true.

Of course, if the TPC wouldn't make demonstrably ridiculous claims about their course, none of this would be necessary. It is still fun to swing the mathhammer, though.

Waggle Room Ryan said...

Mathhammer - I love that term. I'm going to steal it.

Really, a dozen per group, OEG? I was saying in a reply to a reply of this posted at WR that each group would have to dump 12-16 in each to get to that 120K number.

Does that sound right, John?

John said...

Interestingly enough, if you go by our "optimal conditions" and laughably assume that Sawgrass fires off a foursome every 8 minutes (a standard tee time interval) like clockwork, the number of golfers per year on the TPC works out very close to 120,000 (125,064 to be exact). A very suspicious difference of only 4.04%.

So by our ridiculous standard you can make the TPC's number if roughly every single golfer on the course drops only one ball in the water. Of course, if 120,000 people were physically ON the TPC every year I doubt very much the landscape would be fit for a monster truck rally let alone a championship golf course.

But like I said, when I saw that 125,064 number I instantly got very suspicious - it's way too close to the TPC's claim to be coincidence. If I had to guess I'd say that's probably where TPC gets the 120,000 balls a year figure from, but you'd think that people with access to actual course usage statistics could come up with a number that is more realistic.

Because, honestly, does anyone really believe they count the number of balls that they dredge out of the water? How much do you pay someone to do that? Minimum wage, or is that a skilled labor sort of thing?

At any rate, this is what doing math all day for a living gets you.

Katie said...

That's hysterical- a combination of wit, story problem and golf- all things I like!

Anonymous said...

You know, I just read this and had one thought. There would be few greater trophies for a tourist golfer then knocking one in the hole here. It would be fun trying even if you used up a sleeve or two in the process. I could believe a dozen per foursome average. 120,000 balls per year would be 10,000 foursomes per year. 10,000 / 320 golfing days per year is 31 foursomes per golf day. Makes sense to me.