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Phosphorus Rule:
Nutrients in Utah’s Waters

New 2016 Amendment

The Water Quality Board approved rulemaking for an amendment to the 2015 rule that addresses comments received from the regulated community regarding the time line for rule implementation. The amendment also incorporates a voluntary wastewater treatment optimization element designed to encourage nitrogen pollution reductions. Additionally, the amendment provides clarification of the phosphorus discharge cap basis, the rule implementation schedule, and to the requirements for manual collection of composite samples along with minor formatting changes. Comments will be accepted until 5:00 p.m. on February 1, 2016.

Technology-Based Phosphorus Effluent Limits

The Utah Water Quality Board adopted a new rule for control of phosphorus discharges into waters of the state that will become effective January 1, 2015. The Technology-Based Phosphorus Effluent Limits or TBPEL Rule, R317-1-3.3 requires that discharges having reasonable potential to discharge phosphorus implement new water quality monitoring requirements by July 1, 2015 and requires that these dischargers meet specified effluent limits by January 1, 2020.

Proposed Rule for Controlling Nutrient Pollution

Summary of the Proposed Rule for Technology-based Effluent Limits
for Controlling Nutrient Pollution

Proposed Rule

Under the proposed rule, all wastewater treatment plants in the state will play a role in reducing phosphorus discharges into state waters.

Non-lagoon Plants

Treatment plants that do not use a lagoon or pond-based treatment technology, referred to as “non-lagoon” plants in the rule, will be required to produce treated wastewater that contains 1.0 mg/L of phosphorus or less before that water may be discharged. This new requirement becomes effective no later than January 1, 2020.

Lagoon and Pond-based Plants

Generally, lagoon or pond-based treatment plants that discharge into receiving waters cannot reliably meet this 1.0 mg/L phosphorus limit, and the costs to upgrade are considered to be unaffordable at this time. Under the proposed rule, each discharging lagoon will be evaluated to determine the current amount of phosphorus discharged each year—the annual “load” in pounds per year that each plant discharges. The proposed rule would restrict the amount of phosphorus that a plant could discharge to 125 percent times the current average annual total phosphorus loading to the receiving stream.

Once the lagoon’s phosphorus cap has been reached, the owner of the facility would have five years to construct treatment processes or implement treatment alternatives (such as land application) to prevent the lagoon from exceeding its total phosphorus loading cap.


The rule contains several variances to the phosphorus limits for discharging facilities under the following special circumstances:

  • They are currently controlled for phosphorus due to site-specific water quality protection conditions.
  • They can demonstrate that the proposed limitation is not necessary to protect the receiving water quality or its beneficial uses.
  • They meet specific conditions of economic hardship.

To meet these variances and be exempted from the proposed phosphorus limits, the applicable conditions must be demonstrated to the satisfaction of the director of the Division of Water Quality by January 1, 2018. Otherwise, under the proposed rule the treatment plants would need to implement the technology-based limit or loading cap (as applicable) by January 1, 2020.


In addition to the limits on phosphorus discharges, the proposed rule would also require dischargers, with some exceptions, to monitor their influent and effluent wastewater for phosphorus and nitrogen in their various chemical forms. For many facilities, this will be the first time they have gathered information about the amounts of nutrients they are releasing to the environment.

The data collected through this monitoring will be critical to DWQ, scientists, and the interested public for determining the ways in which nutrient pollution from towns and cities may be impacting water quality. These data will also support the good science necessary to permanently protect the waters of the state of Utah.

Rulemaking Process

Changes to Proposed Rule (CPR)

The original rule has been modified twice to incorporate suggestions received during the initial comment period.

Changes to Proposed Rule 1 (CPR 1)

Staff presented their responses to public comments (121 KB)to the Water Quality Board on August 27, 2014, and requested that the Board adopt a Change in Proposed Rule (CPR) to address these concerns. These changes include the following modifications:

  • “Exceptions” in the proposed rule were changed to “variances.” Variances are temporary, discharger specific, and must be revisited not less than once every five years.
  •  The exception that provided an off-ramp for dischargers that could demonstrate that their discharge would not increase the receiving water concentration by 10 percent or more was deleted. Dischargers that believe that their effluent has a minimal or nominal impact on the receiving stream may apply for a variance which allows dischargers to demonstrate that the technology-based limit is unnecessary to protect downstream waters from their effluent.
  • The exception providing an off-ramp for dischargers whose implementation of technology-based limits would result in economic hardship was modified. Dischargers are not completely off-ramped if the hardship criterion is reached; an alternative phosphorus limit will be established that does not result in hardship. DWQ noted that publicly owned treatment works (POTWs) can take advantage of low-interest and grant funding that can enable them to comply with the technology-based limit without exceeding the hardship criterion. Other forms of hardship may occur, and these will be evaluated on a case-by-case basis by the Director of DWQ.
  • A variance was added which allows innovative and alternative approaches to be employed, equivalent to and in-lieu of technology-based limits.
  • Monitoring frequencies were changed to a minimum of monthly sampling for all dischargers. This change increased the required monitoring for dischargers with flow rates less than five million gallons per day.

The Board concurred with these proposed changes and approved an additional 30-day public comment period for CPR1.

Changes to Proposed Rule 2 (CPR2)

During discussions on CPR1, the Board requested information on how these changes would affect industry. Among 64 permits reviewed, staff identified two major dischargers and one minor discharger that will likely be affected by the proposed amendment. Other dischargers were identified that had the potential to discharge phosphorus but could not be definitively evaluated using the existing DWQ database. Staff recommended that the Board delay the implementation of the self-monitoring requirement to July 1, 2015, to allow time for further evaluation of these and other facilities to determine their potential to discharge phosphorus above the 1 mg/L limit.

Staff suggested the following changes and clarifications to the rule:

  • Discharging treatment works that can demonstrate that imposing the technology-based phosphorus effluent limit (TBPEL) would cause economic hardship may apply an alternative technology-based phosphorus effluent limit or phosphorus loading cap that would not cause economic hardship.
  • The Director may authorize a variance to the monitoring requirements.
  • The starting date for self-implementation of nitrogen and phosphorus monitoring was extended six months to July 1, 2015.

These changes give DWQ time to identify industries that may not have the potential to discharge phosphorus due to the nature of their business. The changes will also provide the division with sufficient regulatory flexibility to reduce or remove monitoring requirements for pollutants that are expected to be absent in these industrial wastewater discharges. The changes will further the continued reduction of phosphorus loads into Utah’s waters while reducing potential costs to industry.

The Board approved the changes to the proposed rule at its September 24, 2014, meeting. DWQ opened a 30-day public comment period on these changes that closes on November 15, 2014.

Proposed Rule (Original)

On April 30, 2014, the Water Quality Board gave its approval to DWQ to solicit public comment on a proposed rule (108 KB) that will restrict discharges of phosphorus into surface waters by wastewater treatment plants. The proposed rule was published by the Division of Administrative Rules on June 1, 2014. The 60-day public comment period ran for the original proposed rule ran from June 1, 2014, to August 1, 2014.
A series of public meetings were held across the state during June 2014 to explain the proposed rule (108 KB), answer questions, and solicit public input. The Division of Water Quality encouraged members of the public to attend one of these meetings, submit written comments and provide their input on Utah’s Nutrient Strategy (246 KB). Residents attending these meetings were able to learn more about the ways they can help protect Utah’s water resources.


  • Cost Impacts (541 KB)
    Statewide cost impacts of phosphorus removal under the proposed technology based effluent limits.
  • Economic Benefits (495 KB)
    Gauging public opinion and estimating economic benefits of nutrient reduction.
  • Nutrient Overview (685 KB)
    Why be concerned about nitrogen and phosphorous pollution?
  • Nutrient Strategy (484 KB)
    How does Utah plan to address nitrogen and phosphorus pollution?
  • TBL Rule Implementation (2 MB)
    Surface discharge—nutrient technology based limits.

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