Do Idaho's state CAFO laws preempt county regulation of confined animal feeding operations like dairies and feedlots?
Plain-English summary
Five south-central Idaho county prosecutors (Gooding, Lincoln, Jerome, Minidoka, and Cassia) jointly asked the Attorney General to clarify which level of government, the State or the county, controls the regulation of confined animal feeding operations, or CAFOs. CAFOs are large feedlots and dairies, and the question matters because Idaho's dairy industry concentrates heavily in the Magic Valley counties that requested the opinion. Local residents often want stricter rules; operators often prefer state-level uniformity.
The AG's answer divides the field into two parts: siting (where a CAFO can locate) and operations (how the CAFO runs day to day once sited). On siting, Idaho Code § 67-6529 explicitly directs that "a board of county commissioners shall enact ordinances and resolutions to regulate the siting of large confined animal feeding operations." That siting power lets counties consider environmental risks (setbacks, livestock-density limits, location relative to water supplies, etc.) and to require odor-management plans (Idaho Code § 67-6529D). The Site Advisory Team Suitability Determination Act (Idaho Code §§ 67-6529A through 67-6529G) provides counties an optional state-funded environmental risk assessment to inform their siting decisions. The Site Advisory Team Suitability Determination Act expressly says it does not preempt local CAFO regulation.
On operations, the picture is the opposite. The Idaho Department of Agriculture (ISDA) under the Beef Cattle Environmental Control Act (Idaho Code §§ 22-4901 et seq.) and the dairy waste statutes (Idaho Code § 37-401) operates a comprehensive regulatory scheme covering nutrient-management plans, design and construction of waste systems, and water-quality protection. The legislative findings in those statutes make clear the State intends to occupy the field for ongoing CAFO operations, with explicit invocation of state primacy and federal Clean Water Act compliance. Under Envirosafe Services v. County of Owyhee (1987), a comprehensive state regulatory scheme can imply preemption of local regulation in the same field even without an express preemption clause.
The AG concluded a court would likely strike down a county ordinance that tries to impose its own water-quality, waste-system design, or nutrient-management requirements on an operating CAFO, because those rules conflict with the State's exclusive regulatory framework. But the line between "siting" and "operations" is not bright. A county siting ordinance with environmental conditions tied to the chosen location (a setback from a stream, a maximum density given local groundwater conditions) is likely fine; an ordinance that effectively dictates how the dairy disposes of manure once sited is likely preempted. The AG noted the unhelpful state of the law and recommended legislative clarification of the respective roles.
Currency note
This opinion was issued in 2008. Subsequent statutory amendments, court decisions, or later AG opinions may have changed the analysis. Treat this page as historical context, not current legal advice. Verify current law before relying on any specific rule, deadline, or remedy mentioned here.
Common questions
What is a CAFO?
A confined animal feeding operation, the federal Clean Water Act term for a large concentrated livestock facility (a feedlot, dairy, or hog or poultry operation). Federal regulations define small, medium, and large CAFOs by animal counts. The CAFO label triggers federal NPDES permit obligations and, in Idaho, state oversight under ISDA and DEQ.
What is the doctrine of implied preemption?
Article XII, § 2 of the Idaho Constitution permits city and county regulation that does not conflict with state law. Implied preemption, articulated in Envirosafe Services v. Owyhee County (1987), happens when state law occupies a field so comprehensively that local regulation is "in conflict with state law" even though the state statute does not expressly forbid local rules. Two ways implied preemption can be found: (1) state law has acted in the area "in such a pervasive manner that it must be assumed that it intended to occupy the entire field of regulation," or (2) the nature of the subject matter requires uniform statewide regulation.
Which Idaho agencies regulate CAFOs?
The Idaho State Department of Agriculture (ISDA) is the lead. The Beef Cattle Environmental Control Act (§§ 22-4901 et seq.) gives ISDA primary authority to regulate beef cattle CAFO water quality and waste. The dairy waste provisions in Idaho Code § 37-401 give ISDA the same authority for dairies, with milk permits conditioned on compliance. The Idaho Department of Environmental Quality (DEQ) handles federal Clean Water Act delegation and certain odor-related authorities (the Agriculture Odor Management Act at §§ 25-3801 et seq.). ISDA and DEQ have memoranda of understanding with EPA and the regulated industries to coordinate. Counties have a defined siting role under §§ 67-6529 et seq.
Can a county ban CAFOs entirely?
The opinion does not say outright. But § 67-6529 directs county commissioners to "enact ordinances and resolutions to regulate the siting of large confined animal feeding operations and facilities." A blanket ban (zero CAFO sites permitted anywhere in the county) would arguably go beyond regulating siting and could be subject to challenge. In practice, counties have used setback distances, density caps, and overlay zones rather than outright prohibitions.
What is a nutrient management plan?
A document each CAFO has to prepare and submit to ISDA describing how it manages livestock waste so as to protect water quality. The plan covers application rates, timing, and locations for spreading manure, plus monitoring. Idaho Code § 22-4906 deems an approved plan a "best management practice."
What changed for CAFO operators after this opinion?
The opinion is advisory; it doesn't itself change any statute. It guided county prosecutors and CAFO operators in evaluating which county ordinances were vulnerable to preemption challenge. The AG explicitly recommended legislative action to "more clearly define the respective regulatory authority of state agencies and local government." Whether the legislature acted on that recommendation in the years since would need to be checked against current Idaho law.
Background and statutory framework
Article XII, § 2 of the Idaho Constitution permits county regulation that does not conflict with state law. The Envirosafe Services v. County of Owyhee (1987) decision is the leading Idaho preemption case: Owyhee County had tried to regulate hazardous waste disposal at a regulated facility, and the Idaho Supreme Court held the comprehensive Hazardous Waste Management Act preempted the local rule. The Court's framework asks whether the state has occupied the field through pervasive regulation or whether the subject matter calls for uniform statewide treatment.
The Beef Cattle Environmental Control Act (BCEC Act) at Idaho Code §§ 22-4901 et seq. is the central state authority over beef CAFOs. Section 22-4902 declares legislative intent to "protect the quality of these natural resources" while maintaining a viable beef industry. Section 22-4903 vests ISDA with the authority to regulate beef CAFOs, including all groundwater protection authority delegated from DEQ. Section 22-4906 requires a nutrient management plan for each beef CAFO.
Dairy waste regulation lives in Idaho Code § 37-401, the Sanitary Inspection of Dairy Products Act. ISDA reviews and approves waste system construction plans, requires nutrient management plans, and conditions milk permits on compliance with both ISDA rules and applicable county livestock ordinances. The Dairy Rules at IDAPA 02.04.14.000 et seq. flesh out the requirements.
Odor regulation comes from the Agriculture Odor Management Act at Idaho Code §§ 25-3801 et seq. ISDA leads, with DEQ handling some swine/poultry components.
CAFO siting is the only area where the legislature explicitly assigned counties a defined role. Idaho Code § 67-6529 says county commissioners "shall enact ordinances and resolutions" to regulate CAFO siting and may "reject a site regardless of the approval or rejection of the site by a state agency." The Site Advisory Team Suitability Determination Act at Idaho Code §§ 67-6529A through 67-6529G adds an optional state-funded review process for counties.
Citations
Idaho Constitution: art. XII, § 2.
Idaho Code: §§ 22-4902, 22-4903, 22-4904, 22-4905, 22-4906, 25-3801, 25-3803(3), 37-401, 37-403, 39-4401 to 39-4432, 42-201(2), 67-6529, 67-6529A, 67-6529B, 67-6529C, 67-6529D, 67-6529F, 67-6529G.
Administrative Rules: IDAPA 02.04.14.000 et seq.; 02.04.15.100 et seq.; 02.04.16.100 et seq.; 02.04.18.100 et seq.
Idaho cases: Envirosafe Services of Idaho, Inc. v. County of Owyhee, 112 Idaho 687, 735 P.2d 998 (1987); State v. Musser, 67 Idaho 214, 176 P.2d 199 (1946).
Other authorities: 1983 Idaho Att'y Gen. Ann. Rpt. 69; The Idaho Beef Cattle Environmental Control Memorandum of Understanding.
Source
- Landing page: https://www.ag.idaho.gov/office-resources/opinions/
- Original PDF: https://ag.idaho.gov/content/uploads/2018/04/Opinion08-01.pdf
Original opinion text
STATE OF IDAHO
OFFICE OF THE ATTORNEY GENERAL
LAWRENCE G. WASDEN
ATTORNEY GENERAL OPINION NO. 08-1
To: Mr. Calvin H. Campbell
Gooding County Prosecuting Attorney
Post Office Box 86
Gooding, ID 83330
Per Request for Attorney General's Opinion
You, along with E. Scott Paul, Lincoln County Prosecuting Attorney, Mike Seib, Jerome County Prosecuting Attorney, Nikki Cannon, Minidoka County Prosecuting Attorney, and Al Barrus, Cassia County Prosecuting Attorney, have requested an Attorney General's Opinion regarding several questions, each of which can be categorized as asking whether Idaho state law preempts local regulation of confined animal feeding operations ("CAFOs"). This opinion addresses the over-arching question you have presented.
QUESTION PRESENTED
Do Idaho's state laws pertaining to the regulation of confined animal feeding operations preempt county regulation of such operations?
CONCLUSION
The state CAFO siting laws expressly authorize counties to "enact ordinances and resolutions to regulate the siting of large confined animal feeding operations and facilities . . . ." Idaho Code § 67-6529. The legislature recognized that county regulation is necessary for the purpose of considering the social and environmental impacts associated with CAFOs. Idaho Code § 67-6529B. Thus, even though the legislature has delegated to the Department of Agriculture and the Department of Environmental Quality the responsibility to regulate water quality and waste water management requirements for the ongoing operation of CAFOs, it is unlikely that a court would conclude that state laws pertaining to the regulation of CAFOs fully occupy the field and, therefore, preempt all local ordinances related to similar environmental concerns. For example, county ordinances that seek to ensure the appropriateness of the location of a CAFO in light of the environmental characteristics of a site, such as setbacks or maximum livestock density requirements, are likely to be upheld by a court. County ordinances, however, that seek to directly impose water quality or waste management requirements on the ongoing operation of CAFOs once sited are likely to be found in conflict with, and therefore preempted by, state law. Whether specific provisions of a local zoning ordinance conflict with state laws applicable to CAFOs requires an analysis of the particular ordinance at issue, along with the applicable state laws. Such an analysis is beyond the scope of this opinion.
The lack of clarity with respect to the limits within which local governments may regulate CAFOs unfortunately pits local government and the regulated industry against one another and leads to costly and potentially lengthy litigation. Legislative action to more clearly define the respective regulatory authority of state agencies and local government is warranted.
ANALYSIS
A. Overview of Local Zoning Authority
Article XII, § 2 of the Idaho Constitution provides:
Any County or incorporated city or town may make and enforce, within its limits, all such local police, sanitary and other regulations as are not in conflict with its charter or with the general laws.
While land use planning is primarily within the purview of local government, county ordinances that are in conflict with the general laws of the state are preempted. A conflict between local and state law may arise in a number of different situations. There may be a direct conflict between the two laws, which usually occurs when local law expressly allows what the state disallows and vice versa. State v. Musser, 67 Idaho 214, 176 P.2d 199 (1946); Envirosafe Services of Idaho, Inc. v. County of Owyhee, 112 Idaho 687, 689, 735 P.2d 998, 1000 (1987). A conflict may also arise when state law addresses an entire field or area of regulation. Since none of the Idaho statutes applicable to beef or dairy CAFOs expressly preempt local regulation of CAFOs, this opinion analyzes and applies the doctrine of implied conflict preemption.
B. Implied Preemption
Idaho has adopted the doctrine of implied preemption, set forth by the Idaho Supreme Court as follows:
Where it can be inferred from a state statute that the state has intended to fully occupy or preempt a particular area, to the exclusion of [local governmental entities], a [local] ordinance in that area will be held to be in conflict with the state law, even if the state law does not so specifically state.
Envirosafe Services of Idaho, Inc. v. County of Owyhee, 112 Idaho 687, 689, 735 P.2d 998, 1000 (1987).
C. Pertinent Acts and Statutes
The Idaho Code contains several acts and statutes that authorize state agencies and counties to regulate various aspects of dairy and beef cattle CAFOs. The Beef Cattle Environmental Control Act (Idaho Code §§ 22-4901 et seq.) authorizes ISDA to regulate beef cattle animal feeding operations to protect state natural resources, including surface water and ground water. Each beef CAFO is required to have a nutrient management plan, and once approved, the plan "shall be implemented and considered a best management practice." Idaho Code § 22-4906. The dairy waste statutes at Idaho Code § 37-401 condition the issuance of milk permits on compliance with applicable county livestock ordinances and require nutrient management plans approved by ISDA. The Agriculture Odor Management Act, Idaho Code §§ 25-3801 et seq., gives ISDA authority over odors from beef CAFOs and other agricultural operations.
Although state agencies (particularly ISDA and DEQ) have a large role in regulating CAFOs, the Idaho Legislature has also recognized the role of counties in siting of CAFOs. Idaho Code § 67-6529 specifically requires that "[n]otwithstanding any provision of law to the contrary, a board of county commissioners shall enact ordinances and resolutions to regulate the siting of large confined animal feeding operations and facilities, as they shall be defined by the board ...." Idaho Code § 67-6529(2). Section 67-6529 also provides that a county "may reject a site regardless of the approval or rejection of the site by a state agency." This section applies to both dairy and beef CAFOs.
The Site Advisory Team Suitability Determination Act, Idaho Code §§ 67-6529A et seq., allows a county to call upon ISDA to form a site advisory team to assist counties in environmental evaluation of proposed CAFO sites. Notably, the Act specifically provides that "this act does not preempt local regulation of a CAFO." Idaho Code § 67-6529D(3).
D. Analysis
Since none of the statutes cited above expressly preempt local regulation of CAFOs, the issue presented turns on whether the legislature impliedly preempted local regulation. Implied preemption may occur if the state fully occupies the field of regulation, in which case any local ordinance in the field is preempted. In addition, even when the state has not fully occupied the field, implied preemption may occur when a specific county ordinance is found to be in conflict with state law.
Unlike the situation considered in Envirosafe, however, state law provides specific authority to counties to regulate the siting of dairy and beef cattle CAFOs. Idaho Code §§ 67-6529 through 67-6529G. These siting statutes direct that counties consider the "social and environmental impacts" arising from the location of CAFOs. Counties are authorized to review and take into account information regarding the environmental risks posed by a CAFO. Idaho Code § 67-6529G. This obviously could include risks to ground and surface water quality and air quality. In addition, counties are specifically authorized to require CAFOs to submit odor management plans. Idaho Code § 67-6529D.
In light of the significant role provided for counties in the siting of CAFOs, it is unlikely that a court will find that local regulation of the entire field of CAFO regulation is preempted. On the other hand, the legislature's express delegation of regulatory authority over operational aspects of CAFOs to the Department of Agriculture and the Department of Environmental Quality suggests that a court may, under a conflict analysis, determine an ordinance imposing restrictions that unduly interfere with state operational requirements for CAFOs is preempted. There is no bright line between what constitutes a siting condition and an operational condition.
CONCLUSION
Because the legislature has authorized both the counties and the State to regulate CAFOs, and because these authorities overlap, it is unlikely that a court would conclude the State has completely occupied the field of CAFO regulation or that state law provides an exclusive regulatory program that preempts all local regulation. Although counties have authority to regulate siting of dairy and beef cattle CAFOs, county ordinances that seek to impose operational constraints on the ongoing operation of a CAFO after it is sited are likely preempted. Each ordinance must be analyzed separately along with applicable state law to determine whether such a conflict exists.
Dated this 1st day of August, 2008.
LAWRENCE G. WASDEN
Attorney General
Analysis by:
ANGELA SCHAER KAUFMANN
DOUGLAS CONDE
Deputy Attorneys General