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Understanding the gravity of gravity—the role of science and scientists in establishing strategic policies.
E. Allen Stewart III P.E.—August 2017

 So far, so good!

How's it going?

Of course this is an absurdity—we all have recognized the dangers of falling since we accidentally flipped out of our crib as infants. We all accept the science of gravitational influence. But it is this absurdity that carries the desired message.  

Let’s say that this third possibility is true, and the man really does not understand the relevance of gravity. In such a case, the man would have been well advised to consult with a scientist before making a decision to jump off the building. It would have saved his life. Or perhaps he did consult with a scientist, but did not trust or believe him/her. 

Today, we are like the falling man, with our political system setting policy and making decisions without first seeking or accepting sound objective scientific review. Are there long-term dangers that such a review might disclose - dangers which otherwise would not be recognized by policy-makers who are not scientists? 

Let me share with you a personal experience that may help bring clarity to this issue. I remember the passage of the Clean Water Act –PL95-217 in 1972.  One of its stated goals was that the “discharge of pollutants into navigable waters be eliminated by 1985.”  In an effort to achieve this goal, Section 201 of the Act was established to facilitate federal funding of effective regional wastewater collection, treatment and disposal facilities.

As a young Florida engineer in 1976, I was involved in helping local entities secure federal “201” monies for wastewater upgrades, and in designing and implementing these regional programs. It was an exciting time for young professionals such as me, for most of us involved in these projects felt that we were making positive strides towards more effective protection of Florida’s waters.

One thing I remember clearly was discussions related to the fate of septic tanks. There was considerable support in the scientific literature that septic tank densities over 1-2 residential septic tanks per acre could generate serious nutrient (mostly nitrogen and phosphorus) pollution within the contiguous groundwater. Typically wastewater is generated at the rate of about 100 gallons per person per day. Considering the nation’s average family size of 2.6 people, the average septic tank flow per acre therefore would be expected to be no more than 520 gallons per acre.

I was, and remain, particularly interested in the relationship between nutrient levels and eutrophication of surface waters. It was clear to those of us most familiar with the Florida environment with its highly permeable sands, its high groundwater levels, the sensitivity of its surface waters to excessive nutrients, and the importance of the Upper Floridan Aquifer as a potable water source, that establishing septic tanks at high densities has the potential of becoming a serious nutrient pollutant source and was not a good fit for Florida, particularly at high densities. 

And yet septic tanks prior to the Clean Water Act (CWA) had proliferated. We were encouraged that this proliferation might stop with implementation of the CWA, considering its support of regional state-of-the-art wastewater treatment plants and the scientific evidence it provided regarding the potential deleterious impacts of septic tanks.

After prolonged argument about septic tanks and much political maneuvering, the dust finally settled, and the Florida legislature passed the 1983 Water Quality Assurance Act. While touted as an Act designed to protect Florida’s groundwater resources, provisions were included that when regional wastewater facilities were not accessible, septic tanks would be permitted at densities of up to 1,500 gallons per acre per day for units on private water systems, to 2,500 gallons per acre per day for units on public water systems. This was three to five times the upper limit as supported by the scientific literature.     

This was sold as a necessary compromise between the science and the economic interests associated with the development sector. This was however not a compromise, but rather a denial of science.

It was really not much different than the falling man trying to compromise with the established rate of acceleration of gravity on or near the earth’s surface. This rate of acceleration has remained constant, it is not negotiable, and it will not change, regardless of what the falling man believes. The science regarding nutrient pollution from septic tanks is also not negotiable. 

This is but one example of PASOP’s Humpty-Dumpty Axiom: Rejecting, ignoring or denying science does not eliminate the inevitability of its influence, and any laws, rules, Comprehensive Plans, regulations, codes, policies, orders, mandates or directives which are based upon a lack of scientific understanding of the issue(s) in question will over the long term likely cost society more than the money it was designed to save. 

What has happened in Florida since 1983? Have septic tanks become a serious water pollution problem? Yes, they have. For example septic tank seepage was suspected as one of the pollutant sources following a series of algal blooms in the Indian River and Mosquito Lagoons in Brevard and Volusia Counties in 2011. In 2016 an even more serious bloom occurred in the Indian River and Banana River Lagoons in Brevard County, causing extensive fish kills—a result of algae-induced oxygen deprivation. And again septic tank seepage along with excessive freshwater flows and agricultural and urban runoff were responsible. 

A greater awareness of the importance of septic tanks as related to nutrient pollution—specifically nitrogen—developed after research by Brian LaPointe of Florida Atlantic University, and others. They used a nitrogen isotope--N-15—as a marker of fecal associated nitrogen, which revealed much of the nitrogen discharging to east coast estuaries such as the Indian River Lagoon was likely from septic tanks or leaking sewage pipes. Needless to say this work has generated controversy, but it is clearly indicative of a significant septic tank role in the stimulation of these destructive algal blooms. 

So what has been the economic impact? Obviously large scale fish kills degrade the fishing industry—both commercial and recreational. They also erode property values. And then there is the cost of rehabilitation. Twenty three million dollars are presently being invested in the removal of accumulated muck from the Indian River Lagoon—an accumulation directly related to heavy nutrient loading, much of it from septic tanks. And there is no real guarantee that this removal will solve the problem. At some point in time the nutrient sources must be addressed—including elimination of high density septic tank use.  

Now here is where the discussion gets interesting. If we are going to deny science in order to attend to such immediate financial concerns as was the case in 1983, should we not have supportive peer reviewed science which justifies such decisions?

Where was the long-term economic analysis that reflected the future impacts of degraded water quality? Where was the assessment of financial benefits to the community which show they are greater than the expenditures that will be required when water quality and human health issues become seriously problematic? Did anyone attach a dollar value to the reduced fisheries; increased threats to human health; diminished tourist activity; lower property values; or the cost of rehabilitation? How was posterity considered?  Apparently, not at all.

At this point let me provide some clarification. Septic tanks are just one source of nutrient pollution, and it should not be thought that elimination of septic tanks will resolve all problems associated with nutrient discharges. For example, the release of high nutrient water from Lake Okeechobee during the summer of 2016 was a critical contributor to harmful algae blooms (HAB) in estuarine and marine environments in Lee County on Florida’s west coast and Martin and St. Lucie County on Florida’s east coast. Much of the nutrients associated with Lake Okeechobee are agricultural in origin, and while there has been some efforts, apparently supported by certain special interests, to discount the importance of Lake Okeechobee discharges and turn attention to other sources such as septic tank seepage, this is not scientifically honest. In examining nutrient loading, all sources need to be identified and quantified on a case by case basis.   

Perhaps the next time our political leaders are confronted with such issues, and are pressured by moneyed interests, they need to be reminded of such past mistakes, and they need to follow good science—or else they and the people they represent run the risk of being Humpty-Dumptied!

And in such cases, we and our posterity will all suffer. If your political candidate, regardless of party, is a Humpty-Dumpty proponent, you might want to think seriously before giving him/her your vote if you truly care about the welfare of future generations.  



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