QUESTIONS AND ANSWERS
During the meeting, the project team identified four major questions that were consistently asked at the participant stations in the room. The following are our answers to those questions:
What all goes into a noise analysis study?
As part of the environmental study, a noise analysis study is underway to determine whether traffic noise impacts would occur from proposed safety and mobility improvements along US 290 and SH 71 in Oak Hill. If so, noise reduction strategies such as sound walls or other approved sound reduction technologies would be considered.
The study is comparing the two proposed build alternatives with the baseline of a no-build alternative to determine whether traffic noise impacts would occur from the improvements. We plan to have preliminary results this fall and will provide full results at next year’s public hearing.
Sound walls are a common noise reduction technology. The Oak Hill Parkway noise study will inform the project team if and where sound walls may be needed, as well as the appropriate heights and lengths of the walls.
To determine where sound walls are reasonable and feasible, the noise analysis considers numerous factors, including:
- Type of land use activity impacted by traffic noise (homes, schools, hotels, etc.)
- Existing noise levels
- Prediction of future noise levels under each reasonable alternative
- Consideration and evaluation of abatement measures to reduce noise impacts
- Consideration of cost and constructability of walls or other approved noise reduction technologies
To determine reasonableness, a combination of social, economic and environmental factors are evaluated, including noise reduction levels, view impacts and cost effectiveness.
To determine feasibility, topography, access requirements, drainage, utilities, maintenance and noise reduction levels are evaluated.
If the study concludes sound walls are reasonable and feasible, input from adjacent property owners would be used in making final decisions about them.
We are often asked about Permeable Friction Course (PFC) pavement in relation to noise abatement. PFC is currently being considered for the Oak Hill Parkway. PFC’s primary purpose is to facilitate faster water drainage off road surfaces to improve safety. This type of asphalt is currently being used on the MoPac Improvement Project and is planned for the SH 45SW project. This kind of pavement also generally results in lower traffic noise levels than standard pavement. However, PFC is not a federally-approved noise abatement measure and is not part of the noise analysis.
The noise analysis is being conducted in accordance with the National Environmental Policy Act of 1969 (NEPA) and 23 CFR 772 Procedures for Abatement of Highway Traffic Noise and Construction Noise.
What type of construction impacts should we expect?
The environmental study will include an analysis of construction impacts, including a review of impacts to noise, air, and water quality. The study will also take into account the direct, indirect, and cumulative impacts of roadway construction on the area.
If the project is approved to move forward into construction and funding is identified, a preliminary timeline follows:
- Construction duration is between 3-4 years, and could start in 2018-2020 if funding is identified.
- The construction contractor will be required to maintain access to all business. Any temporary closures will be coordinated with the businesses and be scheduled to occur when the business is not normally open.
- Some construction related congestion is inevitable due to temporary lane and road closures. Most closures will be timed to occur outside of rush hour and holiday travels. A goal of the construction plan will to be to keep as many lanes open during construction as possible.
What is the environmental impact of the no build, or do nothing, alternative?
The No Build Alternative would not allow for new travel lanes. US 290 and SH 71 would continue to exist as they do today and would continue to have standard, routine maintenance over the next 30 years. Travel times will increase approximately 25-35 minutes over today, and safety and mobility would continue to decline in the Oak Hill area as population increases. Also, the No Build assumes that all other projects in the CAMPO 2040 Plan would be constructed if environmentally cleared and funding is identified.
In the environmental study, the No Build Alternative is considered and compared against the build alternatives per federal regulations.
Where are the lanes elevated in the two proposed build alternatives?
Both Alternatives A and C propose sections of elevated mainlanes in the US 290 corridor in order to bypass the intersections and signals at William Cannon Drive and SH 71.
For both build alternatives, the lanes are elevated:
- On US 290 from near McCarty Ln. to SH 71
- On SH 71 from west of Scenic Brook Dr. to US 290
At the interchange of US 290 and SH 71, the build alternatives differ:
- For Alternative A, US 290 mainlanes are lowered
- For Alternative C, US 290 mainlanes are elevated
Out of the eight miles of proposed roadway, US 290 will be elevated for one half-mile for Alternative A, and one mile for Alternative C. Learn more about the proposed elevated structures here.