Tuesday, September 30th, 2014
Half-True
Associated Industries of Florida
"Large parts of Florida" have experienced "years of below average rainfall."

Associated Industries of Florida on Thursday, February 6th, 2014 in a press release

Business lobbying group says 'large parts of Florida' had 'years of below average rainfall'

Florida may be the Sunshine State, but what really sets it apart is its water -- where it comes from, how much there is and who uses it.

Lawmakers are paying more attention to water policies in an election year. That means the business-backed lobbying group Associated Industries of Florida is also announcing a new group to help the state make decisions about water quality and quantity.

In a Feb. 6 press release, AIF announced the H20 Coalition, a group described only as "stakeholders" who plan to help mold legislation for water laws. The group points out some reasons for this marked interest.

"Years of below average rainfall in large parts of Florida combined with reduced infrastructure spending during the recession, have exacerbated a growing shortfall in water supply across the state, drawing the attention of Florida's businesses, environmental groups, utilities and government," the release said.

It seems like there’s been a lot of rain across the state lately. Is it true swaths of Florida have been experiencing a persistent lack of rain over the years? We decided to examine the rain gauges and find out.

Rain check

The state’s main groundwater supply is the Floridan Aquifer, which also supplies parts of Mississippi, Alabama, Georgia and South Carolina. The aquifer’s network loses water as it is pumped out of the ground through wells or city water systems, and relies on rainfall to recharge water levels.

Andy O’Reilly, a hydrologist with the U.S. Geologic Survey’s Florida Water Science Center in Orlando, says that across the state, anywhere from less than one to 25 or more inches of annual rainfall has the potential to soak into the aquifer, depending on the local geology. Even much of that ends up as runoff in rivers and streams. The rest of the precipitation either evaporates or is used by plants for transpiration.

"Rainfall is the biggest component in maintaining the aquifer on a regional level," he said, noting that the Floridan Aquifer is particularly sensitive to precipitation levels -- and from overpumping by homes and industries during dry spells. 

So the first thing we did was look into statewide rainfall totals. Checking in with the Florida Climate Center provided a quick look at statewide totals over the years.

Over the last 30 years, Florida has averaged a little more than 54 inches of rain per year, among the highest in the country. Going back to 2000, an extremely dry year, there have been five years of below-average rainfall statewide (2012 was the most recent complete year available):

Yr

‘00

‘01

‘02

‘03

‘04

‘05

‘06

‘07

‘08

‘09

‘10

‘11

‘12

Avg

43.2

54.5

59.4

61.1

59.2

62.7

42.6

45.2

55.1

56.0

49.1

48.9

55.5

 

So, five out of 13 years were below average, which is about 40 percent.

We checked the state’s five water management districts, designed to tend to water resources across Florida. AIF said that "large parts" of Florida had below average rainfail, so numbers by district give us a sense of how rainfall measures up on a regional basis.

For instance, the Southwest Florida Water Management District, which extends from parts of Marion County down to Sarasota County, has a 30-year rainfall average of 51.2 inches. For that district, rainfall totals were:

Yr

‘00

‘01

‘02

‘03

‘04

‘05

‘06

‘07

‘08

‘09

‘10

‘11

‘12

Avg

37.8

45.6

56.9

65.9

62.9

55.1

45.8

39.5

50.7

47.5

53.3

46.6

51.1

 

So there were six years out of 13 that were below the regional average, which is about 46 percent.

The South Florida Water Management District, covering the Miami-Fort Lauderdale-Palm Beach metroplex over to Fort Myers and Naples, extending north of Lake Okeechobee into Orlando, has a 30-year average of 51.4 inches. Its rainfall totals were:

Yr

‘00

‘01

‘02

‘03

‘04

‘05

‘06

‘07

‘08

‘09

‘10

‘11

‘12

Avg

39.4

53.2

54.3

53.3

48.4

60.0

40.7

42.8

53.3

48.4

48.9

49.3

52.2

 

There are seven years below that average since 2000, or about 54 percent.

The data is broken down different ways in different districts, but all of them give you a decent idea of which parts of the state are experiencing less rainfall than usual. In the Northwest Florida Water Management District, covering the Panhandle from Escambia County to the western half of Jefferson County, district-wide data isn’t kept, but rather organized by cities where rainfall totals are measured.

In Panama City, for example, the 30-year rainfall average is 61 inches. They’re an example of a location being hit by some below average years lately:

Yr

‘00

‘01

‘02

‘03

‘04

‘05

‘06

‘07

‘08

‘09

‘10

‘11

‘12

Avg

41.2

50.4

49.0

64.7

46.3

52.6

42.5

35.8

57.8

53.6

48.7

38.7

65.8

 

That means 11 years between 2000-12 had below average rainfall, or 85 percent.

What the climatologists say

But do these numbers mean there’s a shortage of rainfall in the state? Climatologist David Zierden with the Florida Climate Center says no. While it’s true there have been some drier years than normal in the past decade or so, there have been plenty of wetter than average years, too. He said 2013 was the 14th or 15th rainiest year on record since 1895.

Tracking average rainfall means "there will be some winners and some losers," Zierden said. Sometimes the totals are above the average, and sometimes they’re below, which is the nature of Florida’s rainfall. This is a pattern that repeats across the state’s climate zones.

He added the state has been in and out of drought over the last decade, but recent years are no worse than 2000 and 2001, which coincided with three dry years of La Nina conditions.

"Here in Florida we’re really dominated by year-to-year totals," he said. "There’s no statistically significant trend at work here."

Those rainfall variances, as inconsistent as they may be, still mean parts of the state have had dry years, and hydrologist O’Reilly said they still could affect the aquifer. That’s because the recharge rate is not a direct ratio to the rainfall total; for example, a 20 percent decrease in rainfall could mean quite a bit more than a 20 percent decrease in the recharge rate.

Overall, the accumulated effects of rainfall deficits and surpluses combine with the rate at which people pump water out of the aquifer to affect the water supply’s long-term balance, he said.

The AIF press release doesn’t mention overpumping from the aquifer as part of the problem maintaining the water supply, but some experts say that would be the real driver of any shortfalls. And commercial interests, especially agriculture, are responsible for most of that overpumping during dry periods.

Tom Swihart, the former head of the Office of Water Policy in the Florida Department of Environmental Protection, says not only are estimates of future water supply shortfalls historically too high, but currently funded water projects all but meet those goals. Water usage by residents is on a downward trend as well, not just in Florida, but nationwide. But even keeping that in mind, ensuring quality should take precedent over quantity, Swihart said.

"All of this concern about water supply deflects attention from the much more serious problem of excessive nutrients in Florida waters," he said, referring to the proliferation of fertilizers, pesticides and dangerous chemicals in the water supply from the industries for which AIF lobbies. "That truly is a statewide issue and needs urgent attention."

Our ruling

The Associated Industries of Florida said in its press release that "large parts of Florida" have experienced "years of below average rainfall." While parts of Florida have had below-average rainfall, we also saw years of above-average rainfall. Climatologists told us the state overall is doing fine, thanks to the years when it was above average. Most recently, 2013 was the 14th or 15th rainiest year on record since 1895.

While the record on rainfall is mixed, there are other issues that affect water levels in the aquifer. Overpumping for residential and commercial uses, especially during dry spells, has a lot to do with the dwindling water supply as well, but AIF, which lobbies for business interests that pump from the aquifer, makes no mention of that.

The claim is partially accurate, but leaves out important details. We rate the statement Half True.