Storm-Season Preparedness in Northern California for Businesses with Large Commercial Generators

Northern California’s storm profile is unique: atmospheric river downpours, damaging wind events, and occasional freezing snaps can stack up into extended outages right when your operations are most exposed.

 If you run a large commercial generator, storm prep isn’t just about “does it start?” It’s about will the whole emergency power system (EPS/EPSS) carry critical loads safely for days, with minimal downtime and no surprises for the Authority Having Jurisdiction (AHJ), insurers, or your customers.

Below is a practical, operations-first guide to get your site storm-ready, including vertical-specific checklists for different kinds of facilities.

1) Start with a 3-Phase Plan: Before, During, After

Before the storm (30–7 days out)

• • Site risk walk: Inspect roof drains, yard drains, and swales; clear debris so rain doesn’t pond near the generator pad, fuel tanks, or electrical gear. Verify enclosure weatherstripping and rain hoods.
  • Fuel & fluids:
    • Diesel: Top off main and day tanks; schedule fuel polishing if storage > 6 months. Add anti-gelling/winterization additive if temps may drop near local cloud/pour points.
    • Natural gas: Confirm utility curtailment risks and valve positions; ensure regulators are shielded from wind-driven rain and debris.
    • Coolant: Confirm glycol mix and freeze protection; inspect hoses and clamps.
  • Batteries & heaters: Load-test batteries; verify block/jacket heaters and enclosure heaters are on dedicated circuits and holding setpoint. Cold batteries = hard starts.
  • Air & exhaust: Check louvers/dampers for free movement; confirm bird/rain guards on stacks, and that exhaust is clear of potential snow/ice shedding zones.
  • Electrical readiness: Exercise ATSs (preferably bypass-isolation rated where installed), verify labeling, and confirm selective coordination hasn’t drifted after panel or breaker changes.
  • Runtime planning: Stage fuel deliveries or NG contingencies; target 72 hours minimum runtime without resupply if your risk profile warrants it.
  • Parts & tools: Stock belts, filters, fuses, oil, coolant, rags, spill kits, absorbents, and a flashlight/IR thermometer kit. Confirm vendor call-down list and rental bridging agreements.
  • Records & compliance: Keep your NFPA 110 ITM logs, start/transfer test records, and corrective actions current; have one-lines available for responders and technicians.

During the storm

• • Protect intakes: Keep snow/leaf screens clear; monitor for water ingress around doors, conduit penetrations, and cable trays.
  • Remote monitoring: Trend coolant temp, battery voltage, load %, and alarms. If you don’t have telemetry, establish manual check-ins every 2–4 hours for extended events.
  • Fuel discipline: Track burn rate vs. deliveries; for diesel, watch for filter restriction (water/biologicals stirred by sloshing tanks).

After the storm

• • Post-event inspection: Look for water lines inside enclosures, wet filters, soot or exhaust leaks, and evidence of salt spray on coastal sites.
  • Oil & coolant sampling (if the unit ran long hours).
  • Root-cause fixes: If you saw nuisance trips, overheating, or starved intakes, fix now—don’t wait for the next front.

2) Prepare for NorCal’s Storm Types

A) Torrential Rains (Atmospheric Rivers)

• • Drainage management: Confirm the generator pad is crowned or drains away; add gravel skirts or French drains where water accumulates.
  • Ingress control: Seal conduit penetrations; check door sweeps; verify louver rain-hood integrity.
  • Fuel tank protection: Ensure vents and emergency reliefs are shielded from vertical rain. For underground tanks, verify sump pumps and sensors.
  • Moisture & controls: Desiccant packs or space heaters in enclosures reduce condensation on control boards. Keep spare control fuses on hand.
    

B) Heavy Winds

• • Airflow stability: Wind can starve intakes or cause recirculation of exhaust. Confirm wind-rated louvers and sufficient make-up air paths.
  • Debris mitigation: Trim nearby trees; strap/secure loose equipment and temporary covers that could be sucked into intakes.
  • Anchorage & clearance: Verify enclosure and tank anchorage; keep the 5-foot working and ventilation clearances free of storage (also makes the AHJ happy).

C) Freezing Conditions (Yes, it happens)

• • Cold starts: Healthy batteries, functioning block heaters, and correct oil viscosity are non-negotiable.
  • Coolant chemistry: Maintain recommended glycol concentration and test freeze/boil points.
  • Fuel gelling (diesel): Blend winterized fuel or add anti-gel; keep filters warm where possible; consider heated lines/day tank heaters on higher-risk sites.
  • Icing controls: Check that louver heaters or thermostats are operational if installed; ensure snow/ice won’t block exhaust paths.

3) System Readiness Beyond the Engine

Your generator is only as reliable as the system around it:

• • Transfer Equipment (ATS/STS): Confirm UL 1008 rating, neutral configuration (3- vs 4-pole), and exercise each switch. Test alarms and controls.
  • Distribution & Coordination: Review breaker settings and upstream/downstream device coordination—especially if you’ve added loads or changed panels.
  • Grounding/Bonding: Verify whether your ATS makes the generator a separately derived system; check bonding/grounding jumpers and electrode continuity.
  • Ventilation & Heat Rejection: Ensure radiator discharge isn’t blocked by temporary storm shields; confirm fans and shutters cycle correctly.
  • Load bank testing: If you haven’t performed an annual loaded run, consider a pre-storm verification to reduce wet-stacking and reveal marginal components.
    

4) Vertical-Specific Checklists

Healthcare & Senior Care

• • Life-safety prioritization: Map true Emergency (Article 700) vs. Legally Required Standby vs. Optional loads; confirm emergency feeders are identified and protected.
  • Run drills: Conduct a short after-hours transfer test with clinical leadership present.
  • Fuel assurance: Minimum 72-hour plan; pre-approved delivery windows with vendor ID and gate access.
  • Quiet hours & fumes: Verify exhaust routing away from patient entries, fresh-air intakes, and ambulance bays during prolonged runs.

Data Centers & Critical IT

• • Stack coordination: UPS → generator → ATS/STS transfer scripting should be practiced. Check ride-through settings and genset start delays.
  • Thermal planning: Ensure HVAC/Economizer modes work on generator power; confirm breakers sized for in-rush of chiller/CRAC restarts.
  • Spare parts: Stock air filters, belts, coolant, and fan contactors; confirm a second-call vendor in case your primary is overloaded.

Manufacturing & Warehousing

• • Process loads: Identify motors with high in-rush; consider staggered restart sequences and soft starters/VFDs.
  • Safety circuits: Confirm e-stops, lighting, and fire protection systems are on the right branches and actually restart on generator power.
  • Dock ops: If power is intermittent, plan for safe dock door/leveler operation and battery backups for scanners/routers.

Hotels, Multifamily, & Commercial Campuses

• • Egress & elevators: Ensure code-required lighting, fire alarms, and designated elevators transfer reliably; post tenant guidance for controlled usage.
  • Comfort vs. capacity: Decide ahead of time what you’re willing to support—lobbies, refrigeration, limited HVAC—so loads don’t trip the system.
  • Noise & neighbors: Extended runs may trigger complaints; document allowable dB levels and quiet hours if applicable.

Schools & Campuses

• • Shelter operations: If you may serve as a warming/cooling center, pre-plan load shedding vs. extended runtime.
  • Comms: Test paging/PA on generator; ensure radios and satellite phones are charged and staged.

5) People, Communication, and Documentation

• • Call trees & roles: Publish a simple chart: who calls fuel, who calls the tech, who authorizes load shedding, who talks to the AHJ.
  • Shift coverage: If storms hit overnight/weekend, schedule on-call staff in advance.
  • Safety brief: No entry into enclosures without PPE; lockout/tagout procedures posted; “no hot refueling” policy except by trained vendor with permits.
  • Logs: Record start/transfer times, fuel levels, alarms, and interventions. Clean, current logs reduce inspection friction and insurance issues.

6) Upgrades To Consider

• • Bypass-isolation ATS: Lets you maintain the switch during a storm without dropping loads.
  • Remote monitoring: Add cellular/dual-path telemetry for real-time alerts and trending.
  • Sound/airflow kits: For wind-driven rain or coastal salt spray, consider upgraded louvers and corrosion-resistant components.
  • Fuel quality program: Scheduled polishing/biocide for diesel sites with long storage times.
  • Rental connection cabinet (Cam-locks): Fast, safe tie-in to a temporary generator if the primary unit is down.

Quick Pre-Storm Checklist (Print This)

• • Drains clear; enclosure weathertight; penetrations sealed
  • Fuel filled; diesel treated/polished as needed; NG supply checked
  • Batteries load-tested; block/enclosure heaters verified
  • Air louvers/dampers free; exhaust rain caps/guards intact
  • ATS exercised; alarms tested; labels updated
  • Breaker coordination and grounding/bonding spot-checked
  • Spare parts, fluids, filters, spill kit on site
  • Vendor contacts confirmed; fuel and rental bridging ready
  • Remote monitoring live; manual check cadence set
  • Logs, one-lines, and permits accessible for AHJ/insurer

Final Word

Storms in Northern California are becoming more intense and less predictable. A generator that simply “starts” isn’t enough. You need a system that breathes, transfers, cools, and runs clean for as long as the grid stays dark. 

Prep now, test under realistic conditions, and treat each storm as a rehearsal for the next one. If you don’t have the internal bandwidth, partner with a qualified generator service team to execute this checklist, correct deficiencies, and stand ready during the event.

Call GenServe for immediate dispatch, or readiness-check your site with a no-obligation assessment.