Highway 411 Traffic Study Warns of Growing Congestion Risk as Gross Residential Seeks Approval for 524‑Unit Development
Blount County — A March 2026 traffic impact study prepared by CDM Smith Inc., a Knoxville‑based engineering and planning firm, has identified a significant and persistent congestion risk on Highway 411 that is expected to worsen regardless of new development. The study was commissioned and paid for by Gross Residential, a long‑established apartment developer headquartered in North Royalton, Ohio, as part of its application to build a 524‑unit multi‑family complex south of Calderwood Highway (US 129).
The report was signed in the document by John F. Gould, listed as a “Registered Engineer – AG CUL TUR – State of Tennessee – No. 22640,” and evaluates traffic conditions surrounding the proposed project.
Major Risk: Northbound Highway 411 Queues Already Exceed 400 Feet
The most severe risk identified in the study is the northbound through‑movement congestion on Highway 411, where traffic already backs up more than 400 feet during peak hours. This condition is documented in the section analyzing 2026 existing traffic operations, which states that the northbound movement “approaches capacity and can experience queues in excess of 400 feet during the peak hours.”
The study shows that this congestion:
- Exists today
- Worsens under background growth (2035)
- Worsens under project conditions (2033–2035)
- Persists even after mitigation
- Occurs with or without the proposed apartment development
Highway 411 is a Principal Arterial on the National Highway System, carrying more than 23,000 weekday vehicles, making queue spillback a corridor‑level concern rather than a site‑specific issue.
Why the Risk Matters
The 400‑foot queue length is long enough to:
- Block left‑turn bays
- Interfere with right‑turn lanes
- Disrupt signal operations at US‑129
- Create multi‑cycle delays
- Increase crash exposure
- Reduce corridor reliability for regional traffic
The study notes that background traffic growth alone is sufficient to push the Highway 411/Calderwood Highway intersection toward unstable operations, with volume‑to‑capacity ratios rising above 0.90 in multiple peak‑hour conditions.
Proposed Remediation: Dual Southbound Left‑Turn Lanes
To address rising congestion, the study recommends adding southbound dual left‑turn lanes at the Highway 411/Calderwood Highway intersection. This improvement is intended to increase capacity for the southbound movement, which exceeds 300 vehicles per hour during the PM peak — a threshold recognized by TDOT for dual left‑turn justification.
However, the study acknowledges that this mitigation:
- Does not reduce northbound queues
- Does not materially improve AM peak delays
- Does not resolve corridor‑level congestion
The report states that even with the dual left‑turn lanes, “traffic queues… continue to increase with the proposed development,” and that northbound through‑movement queues are expected to grow “with or without the proposed development.”
About Gross Residential
Gross Residential is a privately held apartment development and property‑management company founded in 1920 by the Gross family in Ohio. The company is headquartered at 14300 Ridge Road, North Royalton, Ohio, and operates apartment communities across multiple states, including Ohio, South Carolina, North Carolina, Alabama, and Tennessee.
Gross Residential is owned and led by members of the Gross family, including Ronald Gross and Michael Gross, who oversee development, acquisitions, and property management operations. The company employs several hundred staff across its regional offices and property sites.
Gross Residential is the applicant behind the Highway 411 apartment proposal and the client for the March 2026 traffic study.
Implications for Blount County
The study concludes that while the proposed apartment development does not independently cause failing levels of service, long‑range planning should include capacity enhancements at the Highway 411 and Calderwood Highway intersection to address anticipated area‑wide growth.
The northbound congestion — already exceeding 400 feet and projected to worsen — is identified as the most significant operational challenge facing the corridor.
As Blount County continues to evaluate new residential and commercial projects, the Highway 411 corridor’s existing congestion is likely to remain a central factor in transportation and land‑use discussions.