California State Lands Commission, Marine Oil Terminal Engineering and Maintenance Standards (MOTEMS), a Statewide Risk Based Inspection and Maintenance Framework for Marine Oil Terminals

California has 35 marine oil terminals where nearly two million barrels of oil and petroleum products are moved over water each day (California State Lands Commission, n.d.-a). The California State Lands Commission sets and enforces the Marine Oil Terminal Engineering and Maintenance Standards (MOTEMS), published as Chapter 31F of the California Building Code. Their purpose is to set minimum engineering, inspection and maintenance criteria for terminals in order to prevent oil spills and protect public health, safety and the environment (California Building Standards Commission, 2025). MOTEMS first took effect in February 2006 and are updated on the state's three year code cycle (California State Lands Commission, n.d.-a; n.d.-b).

Approach

Classify each terminal by consequence. Each terminal is placed in one of three oil spill exposure classes (high, medium or low). The class depends on the volume of oil that could be released, the number of transfers each year and the size of the vessels served (California Building Standards Commission, 2025).

Set audit and inspection intervals by condition. A registered civil or structural engineer leads a multidisciplinary audit team that inspects structural, mechanical and electrical systems. The default interval between audits is four years. The team leader may recommend a different interval based on the extent and expected rate of deterioration. The Commission may accept the recommendation or require a different interval (California Building Standards Commission, 2025).

Link underwater inspection frequency to risk factors. The code sets a maximum interval between underwater inspections. The interval depends on the structure's condition rating, its material and whether the environment is benign or aggressive (California Building Standards Commission, 2025).

Rank defects by threat. Each finding gets a remedial action priority. P1 applies to a condition that poses an immediate threat to public health, safety or the environment. P2 applies to defects that pose a potential threat. P3 applies where systems need upgrading to meet the standards or current codes. P4 covers damage or defects that need repair, which can be done during normal maintenance cycles but within one year (California Building Standards Commission, 2025).

Inspect after damaging events. A focused post event inspection follows events such as an earthquake, storm, vessel impact, fire, explosion or tsunami. Operators must notify the Commission and report observed damage and operating restrictions, and submit an action plan within five days (California Building Standards Commission, 2025; California State Lands Commission, n.d.-c).

Results

MOTEMS have been in force since 2006 and have been revised on each three year code cycle, most recently with the 2025 edition effective January 1, 2026 (California State Lands Commission, n.d.-e). The Commission publishes an audit manual with checklists that terminal operators and audit teams use to document compliance (California State Lands Commission, n.d.-d).