Transportation

Traffic Impact Study

A traffic engineer estimates trips from your project and their effect on nearby roads, as required for many approvals. Typical US fees run $5,000 to $100,000 per study, and most projects take 3 to 10 weeks, depending on count timing and agency review. Our drawings, calculations and reports are sealed by a Professional Engineer (PE) licensed in the state where your project is located, ready for permit submission.

Typical US fee$5,000 to $100,000per study

Typical timeline3 to 10 weeks, depending on count timing and agency review

Permit drawingsSealed by a PE

What the work involves

A traffic impact study (TIS or TIA) estimates trips a development will generate, commonly using ITE Trip Generation data, counts existing traffic, analyzes intersection level of service and queues, and recommends turn lanes, signals or other mitigation. Local codes usually set a trip threshold that triggers a study. The study is prepared by a professional engineer experienced in traffic engineering.

When you need it

Development exceeds the local peak hour trip threshold
New access onto a state highway
Rezoning or special use permit with traffic concerns
Agency requests mitigation analysis

What you receive

Traffic counts
Trip generation and distribution
Capacity analysis
Stamped traffic impact study report
Mitigation recommendations

What drives the cost

City of Pleasanton staff reports describe a range of $5,000 to $100,000 with most around $30,000; an industry source cites roughly $10,000 to $30,000 for typical development studies. Simple trip generation letters cost less.

Related calculators

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Frequently asked questions

How much does traffic Impact Study cost?

Across the US, traffic Impact Study usually costs $5,000 to $100,000 per study. City of Pleasanton staff reports describe a range of $5,000 to $100,000 with most around $30,000; an industry source cites roughly $10,000 to $30,000 for typical development studies. Simple trip generation letters cost less.

How long does traffic Impact Study take?

Plan on 3 to 10 weeks, depending on count timing and agency review from signed proposal to stamped deliverables, longer if a site visit, soil testing or a permit review cycle is involved.

Do I need a licensed PE for traffic Impact Study?

In most US jurisdictions, yes. When the work needs a permit, the plans, calculations or report usually must be sealed by a Professional Engineer licensed in the state where the project is located. Every deliverable we issue for permit is sealed that way.

Will I also need a traffic engineer?

Sometimes. Depending on the site, traffic Impact Study can also involve a traffic engineer, transportation planner or land use attorney. We tell you up front which other professionals your project needs and coordinate with them so the drawings agree.

Who do you provide traffic Impact Study for?

Most of our clients for this service are developers, business owners, municipalitys and attorneys. Describe your project and one of our engineers will reply with scope, fee and schedule.

What triggers a traffic study?

Local codes often use a threshold such as a number of peak hour trips. Some agencies require a study for any new highway access.

What is ITE Trip Generation?

A widely used Institute of Transportation Engineers reference with trip rates by land use. Local agencies may require local counts where ITE data does not fit.

Can counts be done any time?

Agencies usually require counts on typical weekdays when schools are in session, which can affect schedules. Counts during holidays or summer may be rejected.

What mitigation might be required?

Turn lanes, signal changes, access restrictions or fair-share payments toward improvements. The agency decides based on the study's findings and local policy.