Florida’s Nutrient Criteria and Administrative Process to Adopt Rules by gox16621


									      Nutrient Water Quality

Eric Shaw
Nonpoint Source Mgmt & Water
 Quality Standards Section
Bureau of Watershed Management
Phone (850) 921-9929
         Nutrient Criteria

Currently, nutrient criteria in surface waters
are narrative.
Several attempts have been made in the past
to adopt numeric nutrient criteria.
Adoption of numeric nutrient criteria requires
formal rulemaking.
      Rule 62-302.300(13), F.A.C.:
The Department finds that excessive nutrients (total
nitrogen and total phosphorus) constitute one of the
most severe water quality problems facing the State. It
shall be the Department’s policy to limit the introduction
of man-induced nutrients into waters of the State.
Particular consideration shall be given to the protection
from further nutrient enrichment of waters which are
presently high in nutrient concentrations or sensitive to
further nutrient concentrations and sensitive to further
nutrient loadings.
      Rule 62-302.300(13), F.A.C.

Also, particular consideration shall be given to the
protection from nutrient enrichment of those presently
containing very low nutrient concentrations: less than
0.3 milligrams per liter total nitrogen or less than 0.04
milligrams per liter total phosphorus.
   Rule 62-302.530(48) Nutrients:
(a) The discharge of nutrients shall continue to be
limited as needed to prevent violations of other
standards contained in this chapter. Man-induced
nutrient enrichment (total nitrogen or total phosphorus)
shall be considered degradation in relation to the
provisions of Sections 62-302.300, 62-302.700, and 62-
4.242, F.A.C. (applies to all classes of waters)

(b) In no case shall nutrient concentrations of a body of
water be altered so as to cause an imbalance in natural
populations of aquatic flora or fauna. (applies to Class I
through Class III waters)
Previous Efforts at Developing
      Nutrient Criteria
           November, 1970
Staff from the Florida Department of Air & Water
Pollution Control, U.S. Geological Survey, and
Florida Game and Fresh Water Fish Commission
met to discuss the possible development of
nutrient criteria
Options discussed included:
– a non-degradation clause
– a percentage of permissible increase over background
– a mg/l increase over background
November, 1970 (continued)

 Based on discussions at the November
 meeting, several recommendations were

   1. Total phosphorus expressed as P, not to
   exceed 0.10 mg/l above background.
   2. Total nitrogen expressed as N, not to
   exceed 0.10 mg/l above background.
   3. Samples to be taken 500 yards from source.
           February, 1976
A report titled “A Review of the Need for Nutrient
Regulation in Florida” was produced by the
Biological Section, Florida Department of
Environmental Protection.
The report noted that “because of the scope and
severity of eutrophication problems in Florida,
there is a critical need for some type of nutrient
regulation to slow the pace of cultural
eutrophication and perhaps even reverse that
 February, 1976 (continued)

The report reviewed eutrophication, the effects of
overenrichment on algae and macrophytes,
nutrient limitation, availability, and utilization,
limiting nutrient concentrations, nutrient ratios,
and nutrient standards (in other parts of the U.S.).
Although no specific nutrient criteria for Florida
were recommended in the report, the report did
point out the need for such criteria.
A draft rule was proposed to limit discharge of
nutrients to freshwater lakes.
Draft rule included measurements of nutrient
concentrations (total N and total P), chlorophyll α,
Secchi depth, and a variety of other physical and
chemical measurements.
Lakes were classified according to their trophic
state (oligotrophic, mesotrophic, or eutrophic).

Nutrient discharges would be limited based on
lake’s trophic classification and ambient
chlorophyll and nitrogen concentrations.
Proposed rule was withdrawn due to inability to
consistently correlate the introduction of nutrients
to impacts, although a relationship was

As part of the 1994 Triennial Review of State
surface water quality standards, the Department
considered ‘criteria’ that looked at “examples of
evidence that imbalance has occurred” under Rule
62-302.530(48), F.A.C.
          1994 (continued)
“Examples” included:
– 1. Chlorophyll-a in excess of 45 micrograms per liter in
  lakes or 15 micrograms per liter in other waterbodies.
– 2. An algal growth potential of greater than 5
  milligrams dry weight per liter in predominantly fresh
  waters, or of greater than 10 milligrams dry weight per
  liter in predominantly marine waters.
– 3. A 25% or greater increase in the number of pollution
  tolerant taxa or in the number of individuals of
  pollution tolerant organisms, when compared to
  background levels of these organisms, where these taxa
  or individuals make up at least 10% of the test sample.
           1994 (continued)
“Examples” included:
– 4. A 25% or greater decrease in the number of
  pollution sensitive taxa or in the number of individuals
  of pollution sensitive organisms, when compared to
  background levels of these organisms, where these taxa
  or individuals make up at least 20%of the background
– 5. The loss of 50%or more of a taxonomic, trophic, or
  functional feeding group compared to background
  levels of that group, where that group makes up at least
  10% of the background sample.
          1994 (continued)

“Examples” included:
– 6. A quantitative stability index of 50% or less for
  major taxonomic groups or functional feeding groups in
  a sample compared to background.
         1994 (continued)

Proposed rule did not provide any guidance for
how exceedances would be determined.
After presentation at several public workshops,
proposed rule was withdrawn due to confusion as
to how it would be implemented.
Nutrient Criteria Rulemaking

Formal rulemaking is necessary for adoption of
statewide numeric nutrient criteria for surface
Nutrient Criteria Rulemaking
 Public workshop(s)
 Legal notice of public workshops in the Florida
 Administrative Weekly (FAW)
 Preparation of a Statement of Estimated
 Regulatory Costs (SERC), if required
 Legal notice of proposed rule in the Florida
 Administrative Weekly (FAW)
Nutrient Criteria Rulemaking

 Formal approval by the Florida Environmental
 Regulation Commission (ERC) at a public hearing
 Formal approval by the U.S. Environmental
 Protection Agency (Region 4, Atlanta)

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