Iowa Terminates Nutrient Criteria Rulemaking

The Iowa Department of Natural Resources (DNR) will ask the Environmental Protection Commission to terminate the rule intended to establish nutrient water quality criteria for lakes to protect recreational uses. Public hearings and consultation with stakeholder groups indicated substantive changes needed to be made to the rule. DNR believes that the planned revisions will change the character of the rule enough to justify a new Notice of Intended Action. The changes will also require some additional research by the DNR making it impractical to amend the current notice. After conducting the research and consulting with stakeholder groups, the DNR will ask the commission to approve a new Notice of Intended Action.

The DNR has also cancelled the two remaining public hearings that were rescheduled for later in March.

Caltha LLP provides expert consulting services to public and private sector clients nationwide to address water quality standards, wastewater permitting and assessing potential impacts of chemicals in the aquatic environment.

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Review of Iowa Lakes Using Proposed Water Quality Standards

The Iowa Department of Natural Resources (IDNR) has proposed a revision to the water quality standards used to assess Iowa lakes. [Read more about the proposed standards] In conjunction with this rulemaking process, IDNR has published a review of existing data sets on Iowa lakes to evaluate how well lakes in the State currently comply with the current and the proposed standards.

The report, “How Many Lakes Will Meet the New Criteria”, compares sampling data from 132 lakes with both the proposed criteria and the criteria currently used to decide whether a lake fully supports swimming. The Trophic State Index (TSI) is used to quantify whether a lake meets the narrative water quality criteria contained in Iowa’s water quality standards such as a lake must be free of nuisance aquatic life. The TSI measures water quality parameters such as nutrient concentrations, transparency and chlorophyll-a concentrations. algae blooms. These narrative criteria apply to all surface waters.

In summary, of the 132 lakes reviewed, 64% do not meet the TSI criteria. A total of 88% of these lakes do not meet the proposed criteria. Most of the lakes that do not meet the proposed criteria would not meet either the transparency or the chlorophyll-a criteria.

Caltha LLP provides expert consulting services to public and private sector clients nationwide to address water quality standards, wastewater permitting and assessing potential impacts of chemicals in the aquatic environment.

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Iowa Lake Water Quality Standards - Secchi disk and Chlorophyll

The Iowa DNR is proposing a rule that sets water quality criteria necessary to protect for recreational uses in lakes. In summary, the rule contains two criteria: Secchi depth of at least one meter and chlorophyll-a not to exceed 25 ug/l. The two criteria must be met at least 75% of the time in order for the lake to be considered to support recreation such as swimming.

The proposed rule 61.3(4) is as follows:

61.3(4) Lake criteria. So that the recreational uses listed in 61.3(1)“b”(1) through 61.3(1)“b”(3) can be supported, the following criteria are applicable to all lakes that have a mean depth of three meters or greater.
a. Transparency. The transparency of the lake as measured with a Secchi Disk shall be one meter or more in at least 75 percent of the measurements taken.
b. Chlorophyll-a. The concentration of chlorophyll-a in 75 percent of the samples analyzed shall not exceed 25 micrograms per liter (μg/l).
c. Water sampling used to determine whether a lake meets the transparency and chlorophyll-a criteria must meet the following:
(1) A minimum of nine sample results are required.
(2) At least three of the samples must be taken from the deepest part of the lake.
(3) All samples must be taken during the months of May through September.
(4) At least three sampling events must be conducted in any one summer recreation season.
(5) Samples must be taken in at least three summer seasons in a five-consecutive-year period.
d. Nitrogen and phosphorus concentrations are among several variables affecting lake transparency and chlorophyll-a levels; however, individual lake and watershed characteristics determine the precise amount of nutrients that can be tolerated within a lake while still attaining the above recreational use criteria. For this reason, nutrient reduction targets will be determined on a case-by-case basis as a result of lake-specific monitoring and data analysis. Lake nutrient response models, such as those used to establish Total Maximum Daily Loads for lakes with transparency or chlorophyll-a impairments, or other appropriate scientific methods will be utilized for this purpose.

Caltha LLP provides expert consulting services to public and private sector clients nationwide to address water quality standards, wastewater permitting and assessing potential impacts of chemicals in the aquatic environment.

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Iowa IDNR General Permit for Well Construction Wastewater Discharges

The Iowa Department of Natural Resources (DNR) is proposed amendments to Chapter 64 – Wastewater Construction and Operation Permits, including a proposal that would require the discharge of wastewater from water well construction and service activities to navigable waters to be covered under a general permit. The proposal would create a National Pollutant Discharge Elimination System (NPDES) General Permit that would require permittees to:

1. Comply with the general water quality criteria,

2. Prepare a pollution prevention plan that includes best management practices (BMPs) to be implemented, and

3. Visually monitor wastewater effluent to determine sufficiency of the BMPs.

The IDNR will be conducting public hearings on the proposed rules at several locations from August 4 through 12.

Caltha LLP provides expert consulting services to public and private sector clients nationwide to address water quality standards, wastewater permitting and assessing potential impacts of chemicals in the aquatic environment.

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Iowa Chloride, Sulfate and TDS Ambient Water Quality Standards

The Iowa Department of Natural Resources (IDNR) is currently proposing to amend Iowa ambient water quality standards for chloride, sulphate and total dissolved solids (TDS). In addition, they are proposing a change to the default hardness value used to calculate ambient water quality standards for many chemicals, especially metals.

The changes being proposed include the following:

• Establish numerical water quality criteria for chloride for the protection of aquatic life uses.
• Establish numerical water quality criteria for sulfate for the protection of aquatic life uses.
• Remove TDS criteria and implementation approach
• Revises default hardness level used for hardness dependent chemical criteria from 100 mg/l (as CaCO3) to 200 mg/L.

IDNR will be accepting comments on these proposed changes until August 14, 2009.

Caltha LLP provides expert consulting services to public and private sector clients nationwide to address water quality standards, wastewater permitting and assessing potential impacts of chemicals in the aquatic environment.

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Chloride - Sulphate - TDS Water Quality Standards in Iowa

The Iowa Department of Natural Resources (DNR) is moving forward on revising Iowa’s water quality standards. Water Quality Standards are the regulatory standards that apply to streams, rivers and lakes. Water Quality Standards consist of three components:

• Designate the use or uses of the waterbody
• Set the water quality criteria for protecting those uses
• Protect and maintain existing water quality

Recently, the DNR began to compile all research related to toxicity of total dissolved solids (TDS), chloride and sulfate in order to update and develop criteria for these parameters. Certain data gaps were identified in the existing data sets which resulted in IDNR conducting some new toxicity tests.

With the availability of new toxicity data, IDNR believes that the minimum data requirements are now met to propose numeric criteria for chloride and sulfate. IDNR plans to also reevaluate the current interim approach for total dissolved solids criteria. The Department is planning on discussing this approach as Information item at the April Environmental Protection Commission meeting.

Caltha LLP provides expert consulting services to public and private sector clients nationwide to address water quality standards, wastewater permitting and assessing potential impacts of chemicals in the aquatic environment.

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Proposed Antidegradation Policy - Extension of DNR Comment Period

The Iowa Department of Natural Resources (DNR) has extended the public comment period on the proposed antidegradation rules to March 4.

Antidegradation policy is one of the three components of Iowa water quality standards - 1) designated uses, 2) water quality criteria to protect those uses, and 3) antidegradation policy. The Iowa DNR is proposing a four-tiered approach, including creating a guidance document that establishes procedures for implementing the antidegradation policy.

The changes being proposed include the following:

1. Incorporate by reference the document entitled “Iowa Antidegradation Implementation Procedure,” which proposes an approach to be followed in assessing and minimizing degradation of Iowa’s surface waters


2. Update antidegradation policy language with four tier approach, and


3. Remove High Quality (Class HQ) and High Quality Resource (Class HQR) designated uses and add several waters to the newly proposed Outstanding Iowa Water (OIW) category.
   

Caltha LLP provides expert consulting services to public and private sector clients nationwide to address water quality standards, wastewater permitting and assessing potential impacts of chemicals in the aquatic environment.

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Iowa - IDNR Draft Antidegradation Policy

The Iowa Department of Natural Resources (IDNR) is proposing changes to its “Antidegradation Policy”. The changes can impact any wastewater discharger in Iowa, but especially new permittees or existing permittees that may wish to increase their discharge in the future. The changes being proposed include:

• Incorporate by reference the document entitled “Iowa Antidegradation Implementation
  Procedure,” which proposes an approach to assessing and minimizing degradation of Iowa’s surface waters,
• Update antidegradation policy language with four tier approach,
• Remove High Quality (Class HQ) and High Quality Resource (Class HQR) designated uses and add several waters to the newly proposed Outstanding Iowa Water (OIW) category.
  

The purpose of the antidegradation policy is to set minimum requirements to conserve, maintain, and protect existing uses and water quality for water bodies that currently meet their water quality standards. The department is required by Clean Water Act to develop and adopt a statewide antidegradation policy and to identify procedures for implementing the policy. Comments on the draft policy are being accepted through January 29, 2009.

Caltha LLP provides expert consulting services to public and private sector clients nationwide to address water quality standards, wastewater permitting and assessing potential impacts of chemicals in the aquatic environment.

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