Lincoln County, SD Fire Regulations: Propane Storage (2026)

Lincoln County Code Chapter 155 superimposes a Water Source Protection Overlay District on every underlying zoning district (§ 155.130(C)) to protect aquifers and wellhead sites used, or potentially used, for public drinking water. Under § 155.132, any use that stores or uses a regulated substance in the overlay needs a conditional use permit, and § 155.133 sets out the engineering standards for storage tanks: metallic underground tanks must be double-walled and cathodically protected, all underground tanks need a continuous leak-detection system with audible and visible alarms, and overfill protection devices must shut off flow before a tank reaches 95% full.

Aboveground stationary tanks need secondary containment, built from clay, bentonite or 60-mil polyethylene, capable of holding 110% of the largest tank's volume. Small agricultural petroleum tanks catch a partial break: a tank of 55 gallons or less is exempt outright, and one over 55 gallons, or a series exceeding 100 gallons, needs secondary containment but not the full tank-by-tank permitting. Propane gets the broadest carve-out of all: § 155.133(A)(10) states flatly that propane tanks shall be exempt from these standards, meaning none of the double-wall, leak-detection, overfill or secondary-containment rules in this overlay apply to an LP-gas tank, residential or agricultural.

That exemption only reaches the Water Source Protection Overlay District as mapped under § 155.131 and filed with the County Auditor and Sioux Falls City Clerk; it does not touch the county's adopted building and fire codes governing propane appliance installation elsewhere in the code. Residents should still confirm placement against the adopted mechanical code before installing a tank near a structure.