Why Interstates Are Different
Interstate highways (I-5, I-80, I-95, etc.) are federally designated highways subject to the Federal Highway Administration's Manual on Uniform Traffic Control Devices (MUTCD). The MUTCD governs what types of signs can be placed on the national highway system, and unofficial roadside memorial signs do not meet federal standards for placement on interstates.
This means that even states with robust memorial sign programs for their regular state highways generally cannot place the same signs on interstates without risking their federal highway funding. Most states have developed alternative approaches for interstate fatalities.
What Each State Does for Interstate Fatalities
States That Offer Alternate Placement on a Parallel State Route
Colorado, Ohio, Minnesota, Tennessee, Washington, and most other states with formal programs offer to install the sign on the nearest state highway when the fatality occurred on an interstate. The DOT will identify an appropriate location and notify the family. This is the most common solution nationwide.
States Where Interstate Signs Are Allowed Under Specific Conditions
A small number of states have obtained or pursued FHWA experimental approvals or have specific programs that allow placement on certain interstate segments. These are exceptions, not the rule, and vary by state and even by specific highway segment. If your fatality occurred on an interstate, ask your state DOT specifically whether any interstate placement is possible — do not assume the answer is no.
States With No Solution for Interstate Fatalities
A few states have programs so strictly limited to state routes that no alternative is offered for interstate fatalities. In these cases, the best options are: informal memorial on the nearest adjacent county road (if permitted), a memorial through the county where the crash occurred, or a non-roadside alternative. See our alternatives guide.
Informal Memorials on Interstates
Informal memorials on interstate right-of-way are almost universally prohibited and removed more aggressively than on regular state highways. The high traffic speeds, narrow shoulders, and federal safety standards make unauthorized placement particularly problematic on interstates. Most state DOTs have specific policies about interstate right-of-way maintenance.
What to Ask Your State DOT
When calling your state DOT district office about an interstate fatality, ask specifically: (1) Do you have any process for interstate fatality memorials? (2) Can you install a sign on a nearby state highway instead? (3) Is there any exception for the specific segment where the crash occurred? (4) What would the fee and process be for an alternate location?