The Governing Framework

North Dakota regulates onsite wastewater under:

• NDAC Chapter 33.1-25-01 — North Dakota Administrative Code, on-site sewage treatment system rules.
• North Dakota Department of Environmental Quality (NDDEQ) — state-level administrator, now with consolidated authority over licensing, permitting, and inspection following Senate Bill 2267 (2025).
• Local Public Health Units — administer field permits under NDDEQ oversight.
• NDDEQ-licensed installers — required for installation of onsite wastewater systems (homeowner self-install on own property for personal use is the primary exception).

Septic Tank Capacity

North Dakota rules establish septic tank capacity based on number of bedrooms or apartment units for residential occupancies, and on occupant load or plumbing fixture units for non-residential facilities. Tables in NDAC Chapter 33.1-25-01 specify incremental capacities for additional bedrooms and fixture units.

Your NDDEQ-licensed installer or designer will reference the current tables for your specific installation. Polyethylene tanks meeting IAPMO/NSF listings and NDAC construction requirements are accepted.

Setback Distances

North Dakota defines setbacks as horizontal separation distances (unless otherwise noted) from systems to wells, rivers, lakes, homes, and property boundaries. Specific distances in NDAC 33.1-25-01 vary by system type, soil conditions, and feature. Your licensed installer applies the correct setbacks for your site.

Regional Considerations

• Red River Valley (Fargo, Grand Forks): Agricultural heartland, highest population density. Mix of municipal sewer (Fargo, Grand Forks) and rural septic. Clay-rich Lake Agassiz sediments complicate absorption-field design — low permeability often requires mounds or alternative systems.
• Bakken oil region (Williston, Dickinson, Minot): Rapid-growth oil-patch communities. New rural residential and commercial septic installations common. Workforce housing and temporary camps have specific commercial/institutional sizing requirements.
• Missouri Plateau (central/western ND): Rolling prairie terrain, variable glacial soils. Standard systems typical; alternative systems where soils perform poorly.
• Turtle Mountains and Pembina Hills: Varied glacial terrain, short construction season due to northern latitude.
• Badlands (western ND): Challenging terrain, bentonite clay concerns, limited flat ground for absorption fields.
• Lake country (Devil's Lake region, Lake Sakakawea shoreline): Shoreland considerations, high-water-table concerns, potentially alternative systems.

Climate and Construction-Season Realities

North Dakota's northern-plains climate affects onsite wastewater construction and operation:

• Deep frost penetration (typically 4–6 feet, deeper in sustained cold) requires tanks, lines, and risers to be installed below frost or insulated.
• Construction season is typically May through October. Winter construction is possible but expensive due to frozen ground.
• Tanks must be designed and sited to avoid freezing during operational low-flow periods — particularly in seasonal cabins and recreational properties.
• Effluent-line insulation and careful vent protection minimize winter operational issues.

Permit Process

1. Contact your Local Public Health Unit. For initial guidance on permit requirements and local overlay rules.
2. Site evaluation. Soil profile, percolation, site restrictions.
3. System design. By qualified designer per NDAC 33.1-25-01.
4. Permit application. Through Local Public Health Unit, with NDDEQ coordination as needed.
5. NDDEQ-licensed installer construction.
6. Inspection before cover.

Frequently Asked Questions

What changed with Senate Bill 2267?

Passed during 2025 session. SB 2267 consolidated licensing, permitting, and inspection authority with NDDEQ and established a statewide installer-licensing framework. Contractors must now hold NDDEQ credentials. The consolidation aimed to standardize practice across ND's varied local public health administration.

Can I install my own system?

Homeowner self-install on own property for personal use is generally allowed as an exception to the installer-licensing mandate. All other installations require a NDDEQ-licensed installer. Verify your specific scope with NDDEQ or your Local Public Health Unit.

Are polyethylene tanks accepted in North Dakota?

Yes, when meeting IAPMO/NSF listings and NDAC 33.1-25-01 requirements. Major OEM rotomolded polyethylene tanks from Norwesco, Snyder, and others are commonly approved. Frost depth and tank rating are important specification considerations.

What about Lake Agassiz clay soils?

Red River Valley clays often perform poorly for absorption-field infiltration. Alternative systems (mounds, pressure distribution, aerobic treatment with reduced-area discharge) are common in clay-rich areas. Plan for alternative system cost on clay parcels.

How do Bakken workforce-housing installations work?

Large workforce camps and man-camps require commercial/institutional wastewater permitting with higher scrutiny than single-family. Temporary installations may use holding tanks with pump-and-haul arrangements; permanent installations need full NDAC 33.1-25-01 compliance including designed treatment and discharge.

Source Citations

• NDDEQ Rules, Regulations, and Policies Portal
• NDCC Chapter 62-03.1-03 Private Sewage Disposal Systems
• NDDEQ Onsite Wastewater Treatment Systems (2025 article PDF)
• NDSU Extension AE-892 Individual Home Sewage Treatment Systems
• NDOWRA SB 2267 Explainer
• North Dakota Septic Pumper Manual

Agricultural Tank Regulations — ND Department of Agriculture

The North Dakota Department of Agriculture (NDDA) administers pesticide and fertilizer regulation under NDAC Title 7 (Department of Agriculture):

• NDAC Article 7-03 — Pesticides, administered by the NDDA Pesticide and Fertilizer Division. Covers registration, dealer licensing, applicator certification, and enforcement.
• NDAC Article 7-04 — Commercial Feed, Fertilizer, and Seed Laws implementation.
• NDCC Chapter 4.1-34 — Pesticide Control Law (statutory backbone).
• NDCC Chapter 19-18.1 — Fertilizer Regulation.
• Bulk storage: North Dakota defaults to the federal 40 CFR 165 Subpart E for commercial pesticide repackaging. Industry best practice is 110% secondary containment for bulk liquid storage.

North Dakota agriculture is dominated by spring wheat, durum, canola, soybeans, corn, and sunflower, with the Red River Valley supporting sugar beets and specialty crops. Bulk ag-retail facilities across the Drift Prairie and Missouri Plateau routinely store liquid UAN, 10-34-0, and field-crop herbicides in polyethylene vertical tanks. Cold-climate specification (low-temperature impact resistance, freeze cycling) is a key design consideration given North Dakota winters.

Oil & Gas Produced Water — NDAC 43-02-03 (Bakken Play)

North Dakota's Bakken and Three Forks play makes this rule family among the most-exercised O&G saltwater frameworks in the United States. The Industrial Commission, through the Department of Mineral Resources, administers:

• NDAC Chapter 43-02-03 — Oil and Gas Conservation rules.
• 43-02-03-53.3 — Saltwater Handling Facility Construction and Operation Requirements. Surface tanks may not be underground or partially buried, must be devoid of leaks, and constructed of (or lined with) materials resistant to produced saltwater, brines, or chemicals.
• Dike requirements: Dikes must be erected and maintained around saltwater tanks at any saltwater handling facility prior to introducing fluids. Dikes and the base material must be of sufficiently impermeable material to provide emergency containment. Dikes must be of sufficient dimension to contain the total capacity of the largest tank plus one day's fluid throughput.
• Storage and handling: All waste, recovered solids, and fluids must be stored and handled to prevent runoff or migration offsite.
• Reporting: Within 30 days of construction or modification of a saltwater handling facility, a sundry notice (form 4) must be submitted with a schematic drawing detailing all facilities, tanks, dike heights, and calculated containment volumes.
• 43-02-03-29.1 — Crude oil and produced water underground gathering pipelines.

Bakken brines run extremely high TDS (often 150,000–250,000 ppm) with significant chlorides, sulfates, barium, and strontium. Polyethylene tank specification must include matched specific gravity rating (often 1.9 SG for Bakken saltwater), resin compatibility, and freeze-thaw durability for the Williston Basin climate. The largest tank + 1-day throughput dike sizing rule is distinctive to North Dakota and significantly more conservative than the 110% industry-standard containment in most other jurisdictions.

Septic System Sizing Deep Dive

North Dakota onsite wastewater falls under NDAC Article 62-03.1 (North Dakota Department of Environmental Quality — Individual Sewage Disposal Systems). Typical capacity table applied on the ground:

North Dakota septic design must account for frost depth (4 to 6 feet typical in the northern tier) and freeze protection for pump-dose systems. Drift Prairie glacial till provides variable percolation. Missouri Plateau sandy soils generally support conventional trenches. Red River Valley clay-lake sediments are notoriously challenging and often require pressure distribution or advanced treatment. Confirm current setbacks and Table values with the NDDEQ or your county before finalizing a site plan.

Chemical Storage Secondary Containment & Spill Reporting

Federal SPCC (40 CFR 112) applies at 1,320 gallons aggregate aboveground oil. North Dakota layers on:

• NDAC Article 33.1-24 — NDDEQ Solid Waste and hazardous material rules.
• NDCC Chapter 23.1-08 — Environmental Response Law (statutory spill reporting framework).
• NDDEQ 24-hour Emergency Notification at 1-701-328-5210.
• NDAC Article 33.1-27 — Underground Storage Tank rules.

Secondary containment for polyethylene chemical tanks should hold at least 110% of the largest tank capacity, except at saltwater handling facilities where the NDAC 43-02-03-53.3 "largest tank plus one-day throughput" rule governs. Above 1,320 gallons aggregate oil, maintain a written SPCC plan. Bakken operators routinely maintain SPCC plus state O&G documentation in parallel.

Permit Pathways at a Glance

• Residential septic: NDDEQ or county environmental health under NDAC Article 62-03.1.
• Pesticide applicator and dealer: NDDA under NDAC Article 7-03.
• Commercial fertilizer: NDDA under NDCC Chapter 19-18.1.
• Oil & gas saltwater handling: NDIC Department of Mineral Resources under NDAC 43-02-03, including the sundry notice filing within 30 days of construction/modification.
• Petroleum UST: NDDEQ under NDAC Article 33.1-27.
• SPCC > 1,320 gal oil aggregate: Federal SPCC plan; NDDEQ spill reporting.

More North Dakota FAQs

I'm building a saltwater handling facility in McKenzie County. What's the dike sizing?

Largest tank capacity plus one day's fluid throughput. File the sundry notice (form 4) within 30 days of construction or modification with a schematic drawing showing all tanks, dike heights, and calculated containment volumes. Use impermeable base material and dike construction.

What specific gravity rating do I need for Bakken brine?

Common Bakken produced water runs 1.1 to 1.2 SG at standard conditions, but some deeper Three Forks brines run higher. Polyethylene tank specification typically calls for at least 1.5 SG rated resin with chloride-resistant construction. Confirm with the manufacturer and your produced-water lab data.

Are there cold-weather design requirements for poly tanks?

No specific North Dakota rule, but industry practice calls for low-temperature impact resistance testing, heat tracing on exposed plumbing, and insulation on tanks holding temperature-sensitive chemistry. Cold-climate brittleness is a real failure mode in the Bakken.

My Red River Valley sugar beet farm has a 2,000-gallon AMS tank. What applies?

Ammonium sulfate solution is a liquid fertilizer regulated under NDDA. Above 1,320 gallons aggregate, check whether the product meets the oil definition under 40 CFR 112 (AMS typically doesn't). Build 110% secondary containment as best practice.

Is there a state-funded cleanup program?

The Petroleum Tank Release Compensation Fund covers eligible petroleum UST releases. Non-petroleum chemical releases are owner liability. Bakken operator E&P waste obligations run with the operator under NDAC 43-02-03.

What's the reporting process for a saltwater release?

Immediate notification to both the NDIC Department of Mineral Resources (operator's district office) and NDDEQ. For any release reaching surface water, also notify the National Response Center at 1-800-424-8802. Document cleanup, sampling, and final disposition.