TL;DR
Plan three routes to your destination before an emergency: primary (fastest normal route), alternate (avoids highways and chokepoints), and contingency (back roads, slower but accessible when others are blocked). Drive all three before an emergency so you know them. Calculate fuel requirements for the longest route and maintain that much fuel in your vehicle. Leave early — roads that are passable at 6 AM may be impassable by noon.
The Case for Multiple Routes
Evacuations fail when everyone uses the same route simultaneously. Interstate highways that carry normal traffic fine become parking lots when every household in a metropolitan area attempts to leave through the same corridor on the same day.
The solution isn't to avoid evacuating — it's to have routes that others won't use. Secondary and tertiary roads are slower but are dramatically less congested during a major evacuation. A route that takes 4 hours under normal traffic might take 5 hours on back roads, vs. 12 hours on the gridlocked interstate.
The Three-Route Framework
Primary Route: Your fastest route under normal or moderately degraded conditions. Usually a major highway or primary arterial. Know every turn from home to destination.
Use when: you're leaving early, before major traffic buildup; conditions don't affect the primary route specifically; route-specific hazards (flooding on the secondary road) make the primary the best choice.
Alternate Route: A route that avoids the primary highway corridor. Usually smaller roads that parallel the primary route. Slower but significantly less congested in most evacuation scenarios.
Use when: primary route is reported congested; primary route passes through an affected area; you have extra time but want to avoid the certain congestion of the primary.
Contingency Route: The route you'd take when both primary and alternate are blocked. Often county roads, farm roads, or even off-road paths for high-clearance vehicles. May be substantially slower. May require specific vehicle capability.
Use when: primary and alternate are both confirmed blocked or compromised; you have a vehicle capable of the route; time allows for the longer travel.
Route Planning Process
Fuel Planning
The most common reason evacuations fail: the vehicle runs out of fuel.
Calculate: your vehicle's maximum range on a full tank. Your contingency route distance. Add 20% margin.
If the contingency route exceeds your range, you need either:
- Pre-staged fuel along the route (stored jerry cans at a waypoint property)
- A confirmed fuel stop along the route
- A vehicle with extended range (secondary fuel tank)
The 1/2 tank rule: Keep your vehicle above half a tank at all times during elevated-alert periods. Fuel shortages during evacuations are common; the people who are running on empty when the emergency starts may not be able to fill up.
Jerry can fuel storage: 5-10 gallons in approved containers stored at home provides significant range extension. Rotate the fuel every 6-12 months (fuel degrades). Use a fuel stabilizer (STA-BIL) to extend storage life to 12-24 months.
Chokepoints to Identify and Avoid
Physical chokepoints:
- Bridges (bridges may close during flooding or damage; identify alternates)
- Tunnels
- Mountain passes (weather-sensitive)
- One-lane bridges or roads with no passing option
Traffic chokepoints:
- Highway on-ramps (traffic will back up from there)
- Major intersections without signal backup power
- Areas near official shelters (roads will be congested)
- Schools and community gathering points
Mark all identified chokepoints on your physical maps. Know which routes have the most critical chokepoints and which are less dependent on any single passage.
Timing Matters
Leave early. The single most important variable in evacuation success is timing. Roads that are passable at 6 AM may be gridlocked by 8 AM and completely blocked by noon after a major event.
Pre-established bug-out triggers (see trigger framework article) determine when to go. The trigger should fire early enough to leave before the peak congestion window.
Rule of thumb: If you hear a mandatory evacuation announcement, you're potentially already in the late window. The people who leave before the official announcement — on their own judgment, before conditions require it — have the easiest evacuations.
En Route Communication
Communicate your route: Before departing, tell your out-of-area contact which route you're taking and your estimated arrival time at the destination.
Check in: Brief check-ins at milestones ("On Route 20 at County Road 45, still on alternate route, ETA 4 hours") allow your contact to relay your status and to sound the alarm if you don't check in.
If routes are blocked: If you're stopped and your route is blocked, communicate the new situation and the revised plan before making a decision. Don't just turn around without telling anyone — your contact may be relaying your position to the destination household.
Physical Maps Are Not Optional
Electronic navigation fails at the worst times:
- Cell service is often congested or down during regional emergencies
- Downloaded offline maps may not cover rural back roads well
- Phone batteries die
A physical road atlas of your state and a detailed county map for your region are irreplaceable navigation backups. Know how to use them before you need to use them under stress.
The person who knows their routes, has physical maps, and leaves early has the most successful evacuation. None of these require special equipment or exceptional preparation — just advance planning.
Sources
Frequently Asked Questions
How many routes do I need?
A minimum of three: primary, alternate, and contingency. Primary is the fastest normal route. Alternate avoids major highways and populated chokepoints. Contingency uses back roads and may require 4WD or significant extra time but is passable when the primary and alternate are both blocked. Each route should have a different geographic profile so they're not all blocked by the same event.
What if I don't have a destination?
Identify one before you need it. A specific family member's home, a pre-arranged host household, or a specific shelter in an unaffected area. 'Drive until I find somewhere safe' is not a plan — it burns fuel, creates uncertainty, and doesn't communicate your location to anyone. A specific destination allows you to communicate your route, estimate arrival, and request help if delayed.
Should I account for traffic in my timing estimates?
Yes, and the answer is usually worse than you expect. Post-disaster traffic multiplied by road damage, accidents, and everyone leaving simultaneously can make a normally 2-hour drive an 8-hour ordeal. Your timing estimates should account for severely degraded traffic. If your primary route is a major highway, assume it will be backed up. Your alternate should avoid that highway.