Ecocentricity Blog: Let's Shed Some Water

By John A. Lanier
Jun 27, 2018 10:30 AM ET
Campaign: Ecocentricity Blog

Ecocentricity Blog: Let' Shed Some Water

You know what word society doesn’t use enough? Datum. In case you aren’t familiar, that’s the singular version of the word data. Most people just use the word data regardless of whether they are talking about a singular piece of information or a collection of information. Technically though, datum is the proper singular noun. I think datum has gotten a raw deal, and I’m hear to do something about it!

Therefore, fueled by the desire to right this wrong and empowered by at least half-decent skills with the English language, I hereby pledge to use the word datum at least 15 times in this blog post. Let’s do it.

I needed a datum the other day. Well, “need” might be a strong word. Let’s say I was interested in a particular datum, as this datum has implications for the resilience of Atlanta. Since I happen to be rather fond of my fair city, I decided to ask the kind folks at the Chattahoochee Riverkeeper for help with this datum.

What was the datum you ask? Happy to share! I wanted to know approximately how many acres per person were in the watershed that provides Atlanta’s freshwater supply. Last time I checked, freshwater is pretty important to a city’s vitality.

Jason Ulseth (their Riverkeeper) and Chris Manganiello (their Water Policy Director) were all over it. Citing the 2017 Water Resource Management Plan for the Metropolitan North Georgia Water Planning District, they first noted the datum that the city’s watershed is 1,040 square miles (effectively the Lake Lanier drainage area). Run that datum through a handy-dandy online calculator and you end up the datum that Atlanta has a watershed of 665,600 acres.

Next, we need the population dependent upon that watershed. They looked at information from the 2010 U.S. Census and overlaid it with a map of the watershed to estimate 3,500,000 people. With that datum, we can just do some simple division to arrive at the datum I sought.

665,600 acres divided by 3,500,000 people equals approximately 0.2 acres per person. Now to me, that’s an interesting and concerning datum. Let me tell you why.

First, 0.2 acres isn’t all that large. For comparison, a football field with both of its end zones is 1.32 acres. That means that 0.2 acres is roughly an area 18 yards long by the width of a football field. Therefore, on average, each person in Atlanta’s watershed should use no more than the amount of rain that falls on 18 yards of a football field.

The second reason I am concerned is because Atlanta has assuredly grown since the 2010 Census. Moreover, every projection for the city suggests that this population growth will continue, all while our watershed stays the same size. That means our watershed acres per person is only going to get smaller and smaller. If the Atlanta watershed population doubles, we’ll be looking at only nine yards on a football field per person.

The good news is that it rains a lot in the south. The bad news is that we are still susceptible to drought. I hope this 0.2 acres per person datum makes you realize just how important water conservation efforts are, not only in Atlanta but in any place with scarce water resources.

Hmmmm. I haven’t hit my quota…. what to do…what to do……..I know! A contrived Dad joke!

How should a dad respond if his daughter says, “I just met a cute guy who’s really good at identifying the three most critical pieces of isolated information in a complex data set. What should I do?”

Answer – Datum datum datum!

Ugh. Even I thought that was awful. Sorry y’all.


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