3/4” - 2” River Rock / Sewer Spec
Washed 3/4-inch to 2-inch river rock (sewer spec) for septic drainfields, drainage, and utility projects. Darby Pit – Driggs is an Eastern Idaho Public Health approved drainfield aggregate source (2026 list).
Material price only. The delivered price, with delivery, tax and fuel surcharge, is below.
Septic drainfield approval
Eastern Idaho Public Health lists Darby Pit – Driggs as an approved drainfield aggregate (drain rock) source on its 2026 Drainfield Aggregate and Construction Media Approved List dated June 26, 2026. Approval means the pit can produce rock to the drainfield specification; the material must stay clean through loading, hauling and installation, and your installer or health district confirms suitability for a specific system.
Eastern Idaho Public Health 2026 approved list (opens in a new tab)Gradation reports
Drainfield aggregate gradation (2025 PDF) (opens in a new tab)These are historical reports, not confirmation of a current load’s suitability. Send us your project specification before ordering specified material.
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