This course will cover the agricultural and urban water quality issues in Florida, their bases, land and nutrient management strategies, and the science and policy behind the best management practices (BMPs). Students will learn to evaluate BMP research and analyze its role in determining practices and policies that protect water quality.
Water Quality and Regulations
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农业可持续土地管理
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从本节课中
Water Quality Issues and Regulations
In week 2, we will take a look at the big picture and some interesting examples, discuss the value of agriculture, and cover the im
与讲师见面
George J. Hochmuth, Ph.D.Professor
Urban and Agricultural Environmental Sciences
Hello again, everybody. Welcome to our third and last lecture for
week 2 in our course. We've so far, visited about 2 large
watersheds and water bodies in, the United States.
And we also focused a little bit more down on the state of Florida.
And our natural resources, and our agricultural industry.
Today I want to step back and take a look at water quality and regulations
pertaining to water quality in this country.
Because I think the history will be useful to us as we move forward and talk about
the different approaches that we, we work with agriculture to help improve water
quality. I want to cover several areas most notably
why do we regulate pollution problems. I want to talk a little bit about the
history, because I think America has a very interesting history in terms of
developing regulation. About water quality and I want to talk a
little bit about the various approaches to water quality regulations and, and how
that relates to what we're eventually going to be focusing on and that's
agriculture. So why do we care?
Well quite frankly and simply, no one likes dirty water.
Water bodies have many functions that we really care about, for example, drinking
water is very important to us. Water bodies are also used for other
purposes. For example, irrigation, fishing,
swimming, and also their important to maintain wildlife habitat.
And society has determined that we want to protect our water bodies from pollution
that would reduce their usefulness. And we'll talk about designated uses so we
have an idea of what we want that water body to do for us, and the kind of state
that we want it in, and we make those decisions.
And so we determine what we want for that water body, and then a process for how we
are going to keep it clean. It's interesting to point out that some
recent research has shown that 80% of our water bodies or 80% of the worlds
population depends on rivers that are affected with pollutants.
And biological diversity is threatened in 65% of the rivers around the world.
So clearly we have some challenges in front of us.
Some of the common water pollutants that we read about and, and will be dealing
with through this course sediment. We've already talked a little bit about
that when we touched on the Mississippi River watershed and the sediment that
could possibly come off of farms in that area.
Nutrients are also a challenge for our water bodies.
There are other pollutants such as bacteria, sewage, various toxic chemicals,
and petroleum, things like mercury contaminants.
Because we're interested mostly in agriculture in this course, we're going to
focus on nutrients, particularly nitrogen and phosphorou and their role on water
quality degradation. The environmental problems that go along
with some of this extra nutrients do lead to problems in our water quality.
And just as an example nitrate nitrogen would be one to look at the US
Environmental Protection Agency has set a drinking standard, a safe drinking water
standard of ten milligrams per liter of nitrate nitrogen as nitrogen, equivalent
to 45 milligrams per liter of nitrates. The reason this was done, it's been years
was because of the socalled blue baby syndrome or methemoglobinemia, which is
where the hemoglobin, because of the presence of nitrate.
Is changed to a form that has a decreased affinity for carrying oxygen, and this is
mostly a problem in infants that are less than three months of age.
But nitrate problems in water are more than health issues for humans.
For example, high nitrate leads to ecosystem threats and ecological
impairments. The ones that we'll talk mostly about have
to do with blooms, excess aquatic plant growth, and dead zones that can happen at
concentrations of nitrate nitrogen even lower than 10 milligrams per liter.
And so, it becomes, we become very interested in how can we manage those
Nitrogen levels in our water bodies at levels that would, are even lower would
impact human health. This whole process is called
eutrophication, and in, ecosystems, the aquatic the response to the addition of
these extra nutrients comes in many forms. And I've listed a few of them here
increased plant growth, algal blooms nuisance aquatic weeds there, the
pollution can also, because of the changes in, in the water quality can lead to
changes in the balance of the, the biodiversity.
So we can have changes in the relative proportions of certain animals for
example. Because plants grow in the water to a
greater level they also die and decompose. And this leads to hypoxia or a low oxygen
level content in the water due to the decomposition process of that organic
matter. And also certain, certain algal blooms can
be toxic, in other words. Certain toxic chemicals can be produced,
and I've given you on your reading, on your reference list a paper that was a
review of some of the toxic algal research.
So these problems, this eutrophication, leads to an impairment of the designated
use of that water body and that's when we become concerned, because what we want
that water body to function as has now been changed because of the addition of
the pollutants. So what happens when these things go
wrong? What can we do.
I mean we've looked at a few of the pressures that people place on resources
on our water body that lead to impairment. So what happens when it's determines that
the water body is not meeting it's designated use.
What do we do? And in sometimes there's a lot of
differences in the way the water bodies and their designation, designated use are
viewed. Because the natural ecosystem can process
nutrients and reach a steady state. But when man comes along and makes a
decision about a water body sometimes our ideas about how that water body should,
should be would be different than in the natural state.
So what do we do with these? Well I think we have to step back and look
at the regulation in, regulation in the United States, it goes all the way back to
the late 1800's with a piece of federal legislation that addressed dumping of
materials into rivers. And this particular rivers and harbor act
is one of the oldest pieces of legislation in the United States.
The Federal Water Pollution Control Act was another act in the middle part of the
last century that again focused on these so called point sources or this
particularly sewage waste from municipal treatment.
The problem continued and in the late 60's led to amendments in this Federal Water,
Water Pollution Control Act and was exacerbated, or things came to a head With
such things as the Cuyahoga River fire in 1969.
Actually this river caught on fire several times over the last several decades.
But things like this, incidences like this led people to just decide that we needed
to finally to do something conclusively about water quality.
Okay, and this was particularly acute during the 60's and early 70's.
In 1970 the National Environmental Protection Act was formed, was signed by
President Nixon, and this actually lead to the development of the, the, the
Environmental Protection Agency, or EPA. Along with, at this same time amendments
to the Federal Water Pollution Control Act were made and in 1972 those amendments
were called and we refer to this act now as the Clean Water Act, it's our, it's our
term, or short term as it were. As for the federal water patrol, Water
Pollution Control Act. The Clean Water Act, or CWA, sets the
basis for much of what we do today to address water quality issues, and there
have been several amendments to it over the years.
If you want to read more about the details on the Clean Water Act, there is
considerable amount of information on the internet.
If you want to read more about the details on the Clean Water Act, there is
considerable amount of information on the internet.
I've given you a few websites here that you can, can peruse at your, at your
leisure. The Clean Water Act, if we go back and
look at the middle of part of the last century.
Of course, this was the time post World War II when people were coming home,
getting to work as it were manufacturing was increasing.
Industrialization was increasing and this was a considerable time of more activity
and more impacts on our water bodies. At this particular time, most of these,
easily identified, sources of pollution, were called point sources, and a point
source is essentially a source of pollutant that is you can envision, say, a
pipe that you can easily see, you can easily get your arms around and
understand. Exactly, where it comes from, you can
measure it and you can control it more effectively.
That's opposed to non-point source pollution which consists of many diffuse
sources points of pollution scattered around the landscape.
The concern early on with the development of these control procedures, this
legislation, was over pollution that was easy to see and deal with.
And those were the points. The Clean Water Act then set about to set
up a structure for laws regulating discharges, these point source pollution.
Non point was not on the radar scope, as it were, at that particular time.
The focus was on point sources. The Clean Water Act sets technology-based
water quality standards for the point sources.
For example, the pollution or the influent coming from a waste water treatment plant
needs to be treated to a certain level before discharging.
And also the process to achieve standards and since then focusing on point sources.
And it's been a lot of success in getting these under control.
These are essentially permitted and managed and, and controlled in that, in
that regard. And there's been a lot of success at
removing point sources as a major contributor to, to water quality problems
in this country. In 1987, the Clean Water Act Amendments
now addressed the non points with the so called, 319 Amendment.
The Clean Water Act mainly addresses surface waters such as rivers, lakes,
streams, estuaries, and there are essentially two components.
Funds to help municipalities and places around the country that are having
problems funds to help them construct treatment facilities and rules and
regulations on water quality. This is a federal state partnership.
The Clean Water Act essentially sets the guidelines, and requires the states to
assess their water bodies and set water quality standards and to implement
restoration processes. The Clean Water Act most point sources
have come under regulation. A few of these examples might be waste
water treatment facilities, solid waste facilities and concentrated animal feeding
operations. These are animal operations that are
treated a little bit differently than farming practices, that we'll discuss a
little bit later on. Most of the pollution problems now left
out to deal with fall under the non-point source.
And examples of these would be nutrients and sediment from farms, from farming
activities, and urban storm water run off. The key tools that the Clean Water Act
has, are regulatory and these are the permits that are required for the, the
point source pollution and non-regulatory. And an example of this would be the
Section 319 that provides grants to states to help these states addresses non-points.
So for example funds can come to the state of Florida and would be used by the
Department of Environmental Protection in this state to help farmers adopt best
management practices for keeping nutrients and sediment on their farm.
And we'll talk about some of those details.
If you were to look at a general flow diagram of how the system is set up and
works. The states would set water quality
standards. They would assess their, their water
bodies as to whether they're meeting these standards.
So for example, is a water body meeting its designated use as a recreational water
body? And the states are required to monitor and
to ask that question. If that water body is not useful for
recreation when it is deemed that it should be then it goes on a list the so
called, 3d, 303d list, or the impaired water bodies list.
This is a list of water bodies that now. The state must develop some strategies for
restoring these water bodies. And part of the process that we'll
describe a little bit more in a second, involves developing total maximum daily
loads for those water bodies. And a total maximum daily load is
essentially the amount of a pollutant that a water body can receive and assimilate
and still maintain it's designated use. For example, as a recreational water body.
Once those TMDLs are determined and calculated, then the state must develop a
plan, to, deal with those sources, to try to get them to be, to be lowered, so that,
that water body can then meet its water quality standard.
If the water body is at a level where it is meeting its designated use, Then the
answer would be yes and it wouldn't be ignored.
But the state would be required to maintain whatever management strategies
are in place to maintain that water quality.
So in essence, this is the process that states must go through.
These water quality standards consist of 3 major areas.
The designated use area, which is where the state determines what a water body
should be used for. The water quality criteria that go along
with that designated use. So for example, the concentration of
nitrate nitrogen in a water body that you need for that water body to meet it's
designated use. And then finally an anti-degradation
policy to keep that water body at the quality level that is required so that it
can continue to meet it's designated use. Designated uses are determined by the
state as those appropriate or maybe could call them desired uses for a water body, a
water body may have more than one designated use.
So it may be designated to function for recreation, for swimming for aquatic
habitat economic factors can be used to set the designated use.
So is it important to the economy of the region to have that water body set for
recreation, recreational uses? This might be an example of the springs in
Northern Florida. But economic factors cannot be used to set
a water quality standard, so if the water body is determined that its, its use
should be for recreation, then there is a level of pollutants that go along with
that. And that, that level cannot be, for
example, a concentration of nitrogen cannot be increased just because it might
be might involve more cost to achieve a lower level.
Now we'll talk about a little bit of things that are done in that regard to
help particularly agriculture, do what it needs to do to maintain water quality
standards that may be costly to, to maintain.
Here are a few designated use categories that we see most commonly in the State of
Florida aquatic habitat, recreation, agricultural use, and we'll focus a little
bit on those water bodies that are for agriculture use.
This picture simply depicts a water that may have several standards set for it
because it has several uses that have been deemed appropriate.
The water quality criteria can be either narrative, such as excessive algal growth.
We want to prevent, excessive algal growth.
Or numerical, more quantitative description of the standards such as no
more than 0.35 parts per million of nitrate nitrogen.
These, these criteria are determined based on a couple of approaches.
One is biological studies where scientists may actually study a range of nutrient
concentrations, and look at the resulting impacts on algal growth and also if those
kinds of studies are not available or easy to do then sometimes a reference water
body is used. So for example, a water body that is very
similar to the one under consideration that is free of algal blooms for example.
What is, what is, what are the characteristics of that water body that
allow it to be free that we need to transfer over to our water body of
concern. Some of the top reasons for getting listed
on the 303d list are shown here. I put these up just mainly to show you
that some of the things that we're going to be focusing on in regards to
agriculture B and P like nutrients and sediment are mentioned very often for many
of our water bodies. They appear very often as pollutants in
our water bodies. So this whole idea of designated use
impairment is a challenging process. It's very, it's not a one size fits all
the reason I say this is because some natural water bodies are, are naturally
eutropic and some of these are actually very good for fishing.
You can see one of the readings on this particular topic.
So this whole process is challenging to go through, because not only do different
people have different ideas about a designated use, but also there is
differing, differing scientific results about what should be the, the criteria to
maintain those uses. So if a water body is not meeting its
standards, then what do we do? It's the state's job, then to evaluate and
list that body, and then work to restore it.
So as we said before, the first step is that, that water body goes on a special
list and a TMDL is set for that water body.
And again, the TMDL is simply the amount of pollutant that a water body can receive
and still meet it's designated use because it can assimilate that much of that
pollutant and still meet it's designated use.
So the states set the TMDLs and of course the EPA approves them.
And if the state's TMDLs are not acceptable or not approved, then the EPA
can come in and set a TMDL for that state. And the goal of this whole process is to
determine that amount of that nutrient that load, that can be applied to that
water body such that, that water body can still meet it's designated use.
And this means that coming up with a total amount of pollutant and then figuring out
what land uses, agriculture, urban, municipal, industrial.
Are out there that contribute to that total load and try to allocate that load
to those various land uses. The TMDL process can sort of be shown
schematically here if you start at the top.
The state assesses the water body to see if it's meeting the designated use.
It verifies that, and makes a decision as to whether to list it or not list it on
the, the 303d list. If it goes on the list, then a TMDL is
set, and the whole process for allocating that TMDL load to the users and this is
done through what's called a Basin Management Action Plan, and so this is a
stakeholder involved process. And it eventually leads to, for example
for farmers, it might lead to the encouragement of them to adopt best
management practices so that they can account for their part of the load, the
TMDL. And so then you implement best management
practices for the agriculture part in that particular watershed and then you monitor
it and then you come back to square one all over again.
So if the monitoring and the assessment indicate that a water body is impaired by
one or more pollutants and it goes on this list, then the state is required to
develop the strategy that will lead to the repairment or the restorement of that
water quality. The elements of a TMDL, allowable
pollutant load or cap and that's the amount that the ecosystem can assimilate.
And then there's typically a margin of safety added to that, and then that, that
load is allocated amongst the sources up in the water shed.
When it comes to the implementation strategies as I said before, this is very,
very difficult because It involves people spending money.
And so for some of the point sources, for example, these permits.
So if there was a concentrated animal feeding operation in this particular
watershed, they would probably be required if they are of sufficient size, to have a
permit for that operation. For agriculture, for farming the section
319 in the Clean Water Act then comes into play, and deals with non-point sources and
would probably provide money to the state to help those farmers adopt best
management practices. And the funding then comes through the
section 319. We'll also talk a little bit later when we
talk more specifically about agriculture some other sources of assistance,
technical assistance and also funding assistance that farmers have access to.
So the non-points, which is where most of our farms are going to fall in this
process, Congress chose not to address non-points through a regulatory approach
and this probably had a lot to do with the fact that these are non-points and they're
scattered and diffuse, and it's very difficult to regulate those kinds of
sources. So rather when it added section 319 to the
Clean Water Act in, as recent as 1987, it created a federal grant program that
provides money to the states. And the state of Florida receives 319
dollars and applies them to best management practice.
Demonstrations, for example the Univeristy of Florida may work with agricutlture
producers using 319 funds to help famers learn about and adopt best management
practices as their part of meeting a TMDL. So what about agriculture?
How does agriculture fit into this whole TMDL picture?
What I would like to do next would be to talk a little bit more specifically about
agriculture pollution, now that we understand where it falls in the federal
scheme of things. And talk a little bit more specifically
about agriculture and the programs that are available to farmers for helping them
adopt BMPs. Okay, so we've come to the end of this
particular part of this lecture, and I just want to, sort of tie things together
with a few take-homes for you. Number one, the United States and Florida
have a strong history of water quality protection, and we've already alluded to
the fact that Florida has to do it. We have a lot of natural resources and we
have a huge agriculture enterprise in this state.
So we have to figure this out. We have to be leaders.
The 1970s were very important in this country for water quality legislation,
that's the Clean Water Act. Agriculture fits under the Clean Water Act
through the non-point source category. Water bodies have designated uses and
water quality standards that are intended, or criteria that are intended to meet
those designated uses. And when water bodies fail to keep the
water quality standards then there is a process for everyone.
To join together to, to understand, to measure, and to come together as far as
how to solve that water quality problem.
