Back to WorkUX Research · Usabilathon

Researching the
Express Lanes Experience.

A mixed-methods UX research study — conducted in-house at Transurban Virginia — to identify critical usability barriers in toll payment, wayfinding, and account management for 127 Express Lane users.

Role
UX Researcher (Lead)
Client
EZ Pass Transurban
Context
Usabilathon Competition
Field Site
Virginia (In-Person)

Research Methods

Mixed-methods survey · Semi-structured interviews · Think-aloud usability testing · Affinity mapping · SUS · UEQ

Research Areas

Toll payment flows · HOV/Express Lane wayfinding · Transponder onboarding · Account management · Penalty communication

Tools

Miro · Notion · System Usability Scale (SUS) · User Experience Questionnaire (UEQ)

Transurban Express Lanes — Payment Flow Prototype

Payment flow prototype — one of the key interaction sequences evaluated during usability testing sessions.

00 / CONTEXT

A government-backed usability challenge.

The EZ Pass Transurban Usabilathon was a competitive UX research challenge in which select teams were invited in-house to Transurban's Virginia offices to evaluate the Express Lanes user experience end-to-end — from pre-trip wayfinding through post-trip account reconciliation.

Unlike a traditional academic project, this was a real-world stakeholder engagement: our research findings were presented directly to the Transurban product and policy team, with the expectation that identified friction points would inform roadmap decisions.

The scope was deliberately broad — covering physical wayfinding, digital account management, transponder onboarding, and penalty communication — reflecting the full user lifecycle rather than a single touchpoint.

127Survey respondents
8Semi-structured interviews
3Core usability domains evaluated
EZ Pass Maryland and Transurban partnership

EZ Pass Maryland · Transurban — the two systems whose integration created the core user experience friction we investigated.

01 / RESEARCH DESIGN

Mixed-methods from the ground up.

We designed a convergent mixed-methods protocol — combining a quantitative survey phase for breadth with a qualitative interview and usability-testing phase for depth. The two datasets were triangulated during synthesis to distinguish widespread systemic issues from edge-case friction.

The survey instrument was distributed to 127 Express Lane users across the Northern Virginia corridor, capturing frequency of use, self-reported pain points, transponder familiarity, and satisfaction proxies. Survey responses were used to prioritize interview topics and identify participant segments for the qualitative phase.

Research plan on whiteboard — Usabilathon kickoff

Research plan whiteboard — scoped and structured in-house at the Transurban Virginia office on day one.

Phase 1 — Generative survey

127-participant quantitative sweep

Structured questionnaire distributed to active Express Lane users. Captured usage frequency, self-reported pain points, and satisfaction ratings to identify the highest-prevalence friction themes before committing interview time.

Phase 2 — Qualitative interviews

8 semi-structured in-depth sessions

One-on-one interviews with Express Lane users representing a cross-section of usage patterns — commuters, occasional users, and first-time adopters. Each session followed a flexible topic guide allowing emergent themes to surface organically.

Phase 3 — Usability evaluation

Think-aloud protocol + task analysis

Moderated usability testing using a think-aloud protocol. Participants were asked to complete representative tasks — adding funds, locating transaction history, understanding a penalty notice — while narrating their reasoning aloud.

02 / SYNTHESIS

From raw data to actionable insight.

Interview transcripts and usability session notes were synthesized using affinity mapping on Miro — grouping atomic observations into first-order themes, then clustering themes into higher-order problem domains. This bottom-up synthesis process ensured findings were grounded in participant language rather than pre-existing hypotheses.

The affinity map revealed four dominant problem domains that cut across multiple user segments and research phases — confirming their systemic nature rather than representing isolated incidents.

Affinity mapping session — Miro board

Affinity map — synthesizing 8 interview transcripts and 127 survey responses into dominant usability themes.

Finding 01 — Wayfinding

HOV entry signage caused consistent lane confusion

Participants consistently misidentified HOV entry points, particularly where Express and General Purpose lanes diverge. Signage cognitive load was compounded by high driving speeds — users reported not having sufficient time to parse multi-element sign compositions before passing the decision point.

Finding 02 — Penalty communication

Physical penalty letters generated avoidance, not compliance

The formal tone and visual density of penalty correspondence caused anxiety rather than motivating resolution. Several participants described leaving penalty letters unopened — a behavioral pattern with direct downstream consequences for Transurban's collections rate and user retention.

Finding 03 — Account management

Cluttered interface obscured primary account actions

The existing account portal presented all functions at equal visual weight — transaction history, auto-replenishment settings, transponder management, and statements competed for attention on a single crowded screen. Participants required significantly more time-on-task than expected for routine actions like adding funds or checking a balance.

Finding 04 — Transponder onboarding

Physical installation instructions generated repeated errors

First-time users consistently misplaced transponders — attaching them below the windshield's metallic band or behind rearview mirror housing — leading to read failures at toll gantries. The included instruction sheet lacked clear spatial reference points, forcing users to rely on trial and error.

Cross-cutting insight

The most consistent underlying theme across all four domains: the system was designed from an operational perspective, not a user mental model perspective. Signage, penalty letters, account structure, and installation guides all reflected how Transurban categorizes information internally — not how a commuter navigating a highway at 65mph processes and acts on it.

03 / EVALUATION

Measuring usability with validated instruments.

To complement the qualitative findings, we administered two standardized usability measurement instruments: the System Usability Scale (SUS) and the User Experience Questionnaire (UEQ). Using validated scales allowed us to benchmark Transurban's performance against established norms and quantify the severity of identified issues with statistical grounding.

Participants completed both instruments immediately following their usability testing session, while task experience was still fresh — minimizing retrospective bias and ensuring ratings reflected actual interaction difficulty rather than general satisfaction.

System Usability Scale (SUS)

10-item Likert-based usability benchmark

The SUS produces a 0–100 composite score where 68 is the industry average. Scores below 68 indicate usability below acceptable thresholds; scores above 80 indicate excellent usability. Our results provided a quantified severity index to prioritize recommendations.

System Usability Scale results

User Experience Questionnaire (UEQ)

Multi-dimensional UX quality assessment

The UEQ evaluates six dimensions — Attractiveness, Perspicuity, Efficiency, Dependability, Stimulation, and Novelty — on a -3 to +3 scale. This allowed us to isolate which UX dimensions were underperforming relative to industry benchmarks, providing targeted design direction beyond a single composite score.

UEQ results across six dimensions

Task Completion Performance

Time-on-task analysis across key user journeys

Time-on-task was recorded for each usability testing scenario. Outlier times — where participants took significantly longer than expected or failed to complete a task — were cross-referenced with concurrent think-aloud narration to identify the specific interface element or content gap responsible for the delay.

Time on task analysis
04 / AUDIT

What the existing system looked like.

A heuristic evaluation of the existing Transurban account portal was conducted in parallel with user research. Evaluating against Nielsen's 10 usability heuristics surfaced structural IA issues that user testing later confirmed through behavioral evidence — providing triangulated confidence in the findings.

Existing Transurban account portal — heuristic audit
Existing account interface — violation of Nielsen's Heuristic #8 (aesthetic and minimalist design). All functions rendered at equal weight with no visual hierarchy to guide task completion.
Improved transponder design concept
Transponder design recommendation — informed by spatial error data from usability sessions.
Prevent fines road signage
HOV enforcement signage — evaluated for legibility and processing time at highway speeds.
Penalty letter sent by Transurban
Penalty letter — formal tone and dense information hierarchy contributed to avoidance behavior.
Invoice letter from Transurban
Invoice correspondence — language and layout tested against plain-language readability standards.
Transponder placement instructions
Transponder placement guide — spatial ambiguity led to a high rate of installation errors in testing.
HOV road instructions article
HOV usage guide — evaluated against plain-language standards; found to assume significant prior knowledge.
05 / RECOMMENDATIONS

Four research-backed design directions.

Each recommendation maps directly to a finding from the research synthesis. Priority was determined by the intersection of prevalence (how many participants experienced it), severity (how significantly it impacted task completion), and addressability within Transurban's product roadmap.

01

HOV wayfinding confusion

Simplify signage through progressive disclosure

Replace multi-element sign compositions with a sequenced signage system — delivering one critical decision cue per sign in the approach sequence rather than all information simultaneously. Prioritize high-contrast color coding aligned with the existing E-ZPass branding system to reduce cognitive parsing time at highway speeds.

02

Penalty letter avoidance behavior

Redesign penalty communication as plain-language guidance

Reframe penalty correspondence from formal legal notices to action-oriented user communications. Lead with the resolution path — a clear, single-step call to action — before any fee or timeline information. Reduce information density by separating penalty notification from payment instructions across two distinct touchpoints.

03

Account management task failure

Restructure account portal information architecture

Apply a task-frequency-based IA hierarchy: surface account balance, add funds, and recent transactions at the top level. Relegate low-frequency administrative actions (statement downloads, transponder settings) to a secondary layer accessible via explicit navigation. This directly addresses the cognitive load identified in the SUS and UEQ Perspicuity scores.

04

Transponder placement errors

Redesign transponder installation guide with spatial anchors

Replace the text-heavy installation guide with a visual-first instruction set using windshield silhouettes as spatial reference frames. Include explicit callouts for common failure zones (metallic bands, mirror housings). Consider a short-form video QR code as a supplementary channel for users who need dynamic guidance.

06 / OUTCOME

Research delivered in-house to Transurban.

The full research synthesis — covering survey analysis, interview themes, usability evaluation data, SUS/UEQ benchmarking, and prioritized recommendations — was presented in-person to the Transurban product and policy team in Virginia. The presentation was structured to map each finding to a business impact metric (collections rate, user retention, support ticket volume) to ground design recommendations in language relevant to the stakeholder audience.

Presenting research findings to Transurban stakeholders
Presenting research findings and design recommendations to the Transurban team — Virginia, in-house.

What this project reinforced.

Reflection

Field research is irreplaceable

Being physically on-site in Virginia — with access to actual signage, penalty letters, and physical transponders — produced a qualitative depth that remote research could not have replicated. The materials themselves were data.

Reflection

Validated scales quantify what interviews describe

The SUS and UEQ gave us the numerical grounding to say 'this is below industry standard' — not just 'users found this confusing.' Stakeholders responded to data-backed severity rankings in ways they wouldn't have to qualitative observations alone.

Reflection

Operational logic ≠ user mental model

Every usability failure we found traced back to the same root cause: the system was organized around how Transurban manages data, not how a commuter makes decisions. Naming this pattern early gave our recommendations a unifying rationale.

The Team

Usabilathon team — Transurban Virginia

Usabilathon team — UX researchers competing in-house at Transurban's Virginia offices.