Residential ISDS review
Identify the health authority for the county and obtain its current application, site-evaluation, testing, and inspection requirements.
Northern Nevada
Percolation testing and septic soil evaluation across Northern Nevada
A practical guide to residential percolation testing, soil profiles, individual sewage disposal system planning, and local review across Northern Nevada's valleys, mountain fronts, rural communities, and remote project sites.
Permitting path
The reviewing authority changes by county and project type
Nevada Administrative Code Chapter 444 provides the statewide baseline for individual sewage disposal systems, but the agency that receives a residential application differs by county. Review may be handled by a local health district, county program, or Nevada Division of Public and Behavioral Health, with separate county or city building and planning approvals.
Commercial, higher-flow, multi-user, tribal, federal, or otherwise specialized projects can follow a different path. Confirm the parcel's land status, project use, sewer availability, responsible health authority, and design professional requirements before scheduling field work.
Building and land-use review
Health approval does not replace county or city planning, building, floodplain, access, well, or grading review.
Commercial or specialized system
Commercial onsite sewage disposal is generally routed through Nevada's environmental permitting program and commonly requires Nevada-licensed professional engineering.
Tribal or federal land
The community name alone cannot establish jurisdiction. Trust, allotted, fee, federal, state, and county land can have different approving authorities.
Understanding test results
Regional geology does not predict a parcel's percolation rate
Northern Nevada sites range from irrigated valley floors and river terraces to alluvial fans, playa margins, volcanic or granitic rock, steep mountain parcels, and remote desert basins. Groundwater, flood conditions, restrictive layers, slope, and available reserve area can be as important as the measured rate.
Parcel-specific: The regulatory thresholds are not predictions for Reno, Carson City, Elko, or any other community. Representative testing and soil-profile observations at the proposed primary and reserve areas establish the parcel-specific design basis.
Faster than 10 is designed as 10 MPI
Under the standard state method, a measured result faster than 10 minutes per inch is not used to reduce the absorption area below the design basis assigned to 10 minutes per inch.
Slower than 60 MPI
State rules require professional-engineer design when the percolation rate is slower than 60 minutes per inch. Any required Nevada engineering document must be under a Nevada-licensed PE's responsible charge.
Above 120 MPI
Results above 120 minutes per inch fall outside the routine soil-absorption trench provisions. The reviewing authority determines whether an alternative or variance path is available.
Field-to-permit process
How percolation testing fits into the project
Local forms and notice requirements vary, but these steps keep the field program connected to the eventual permit submittal.
- 01
Identify the responsible agencies
Confirm county, health jurisdiction, land status, sewer availability, project use, and whether the work is residential or follows a commercial or specialized permitting path.
- 02
Prepare a workable site layout
Show the proposed structure, well and water lines, access, drainage, slopes, primary absorption area, and full-size reserve area before selecting test locations.
- 03
Confirm the approved field method
Coordinate the current application, test-hole count and depths, soil-profile requirements, excavation, water, access, inspection, and scheduling expectations.
- 04
Perform and document field testing
Measure infiltration under the applicable procedure and document the soil profile, groundwater evidence, restrictive layers, rock, fill, slope, and nearby site features.
- 05
Use the results for design and review
Translate the representative field results into the design basis, site plan, supporting report, and next agency step required for that project.
Local planning guides
Northern Nevada community guides
Browse by county or regional authority. The pages explain local planning context, but permit responsibility and field requirements still need to be confirmed for the exact parcel and project use.
Carson City, Nevada4 guides+
Churchill County, Nevada5 guides+
Douglas County, Nevada9 guides+
Elko County, Nevada10 guides+
Eureka County, Nevada5 guides+
Humboldt County, Nevada7 guides+
Lander County, Nevada4 guides+
Lyon County, Nevada9 guides+
Mineral County, Nevada4 guides+
Pershing County, Nevada5 guides+
Storey County, Nevada5 guides+
Washoe County, Nevada12 guides+
Primary sources
Official rules and permitting information
Use these agency sources for planning, then confirm the current process for the parcel and proposed development. Forms, review responsibility, mapped service areas, and local procedures can change.
- Nevada Administrative Code Chapter 444 Nevada Legislature — State residential ISDS siting, testing, and design baseline.
- Onsite Sewage Disposal System Program Nevada Division of Environmental Protection — Commercial and other NDEP-regulated onsite systems.
- Washoe County residential septic information Northern Nevada Public Health
- Carson City residential septic information Carson City Health and Human Services
- Douglas County residential septic information Carson City Health and Human Services with Douglas County Community Development
- Lyon County residential septic information Nevada DPBH Environmental Health with Lyon County Building
- White Pine County residential septic information Nevada Division of Public and Behavioral Health with White Pine County
- Eureka County residential septic information Central Nevada Health District
- Humboldt County residential septic information Humboldt County Building Department
- Lander County residential septic information Lander County Building Department
Common questions
Northern Nevada perc testing
Who reviews a residential septic system in Northern Nevada?+
It depends on the county. A local health district, county program, or Nevada Division of Public and Behavioral Health may handle the residential health review, while county or city building and planning approvals remain separate.
Can a nearby well log or soil map replace a perc test?+
No. Records and mapping help plan the investigation, but they do not establish the percolation rate, soil profile, groundwater separation, or usable primary and reserve areas for the proposed parcel layout.
When is a Nevada professional engineer required?+
Nevada rules require professional-engineer design for certain conditions, including percolation rates slower than 60 minutes per inch, and specialized or commercial projects may also require engineering. The reviewing authority should confirm the required scope.
What information helps you scope a Northern Nevada test?+
Send the address or APN, county, proposed use, any site plan, well information, previous testing or agency comments, and what you intend to build. Calicore can begin with only your contact and parcel information if the process is still unclear.
Start with the property
Not sure what the agency needs?
Send the address or APN and whatever plans, records, or agency comments you already have. If you do not know the required service yet, an engineer can help identify the likely next step.
Ask about your site