GCSD ISO Rating

GCSD has received an improved ISO Public Protection Classification (PPC) of 3/3X!

That’s an improvement from the District’s previous 4/4X classification. For the 2026 evaluation, GCSD was evaluated independently from Tuolumne County Fire, resulting in the improved classification.

Why does this matter?
ISO evaluates the overall fire protection capabilities of a community, not just the fire department.

GCSD earned 71.71 points, placing the District in Class 3. The evaluation recognized the combined performance of the District’s:

• emergency communications,
• fire department capabilities,
• water supply, and
• community risk reduction.

The improved classification may also benefit District property owners. ISO classifications are used by many insurance companies when evaluating property risk and determining coverage and premiums.

And we’re not stopping here!

The evaluation did not yet reflect recent water system improvements that increased fire flow capabilities in Big Oak Flat. ISO used fire hydrant flow data from 2020, prior to those improvements. The District has already coordinated with ISO to flow test the new hydrants and submit updated results, which are expected to increase GCSD’s water supply score.

Continued investments in our water system, hydrant inspection and flow testing, emergency response capabilities, and fuels reduction provide opportunities to further improve our classification in the future.

This is a win for our District and a reflection of the value of continued investment in the essential services that protect our community.