High Density Residential Areas
This indicator measures community noise levels in the high-density residential land use areas. Cumulative noise or community noise equivalent level (CNEL) is a noise measurement based on a weighted average of all measured noise over a 24-hour period. Excessive noise in the Tahoe Region can impact wildlife, visitors’ experiences, and residents’ quality of life. Anthropogenic activities such as construction, vehicular travel, aircraft, recreation, and events are the primary drivers of community noise levels in the Region. Regional programs such as encouraging the use of low-noise pavement and limiting noise during nighttime hours reduce community noise levels in the Region. CNEL is monitored in plan areas across the Region annually.
Status
Average of noise levels in high density residential areas.
Data collected by the Tahoe Regional Planning Agency. Access detailed datasets, including Noise Data Summaries, on Tahoe Open Data.
Evaluation Map
High Density Residential Noise Monitoring Locations
2023 Evaluation
- Status
- At or Somewhat Better Than Target
- Trend
- Little or No Change
- Confidence
- Moderate
Applicable Standard
N16: Background noise levels shall not exceed the following levels: 55 dBA CNEL (Average Noise Level) in the High Density Residential Areas Land Use Category.
Key Points
- Compared to past Threshold Evaluation Reports, there has been little to no change in overall noise levels in high density residential areas.
- Noise levels in each plan area are assessed using the maximum 24-hour noise measurement (i.e., the loudest noise measurement of the day, regardless of duration). Most days most plan areas are within the noise standards, although many plan areas exceed the noise standard on a few days.
- The average noise level across all monitored high density residential areas is well within the threshold standard.
About the Threshold
This indicator measures 24-hour noise levels in the high density residential land use categories in the Lake Tahoe Region. Due to the rural nature of the communities and the pristine natural areas in the Lake Tahoe Region, excessive noise levels have the potential to negatively impact community ambiance, one’s recreational experience and wildlife behavior. In addition to existing federal, state, and local noise control regulations, an effort to address these noise level impacts, TRPA adopted 24-hour noise threshold standards, or community noise equivalent levels (CNEL), for all land use categories, plan areas, and transportation corridors of the Region. TRPA and local jurisdictions review proposed public and private projects to determine if the project would result in increases in existing CNEL that would exceed applicable standards (TRPA Code of Ordinances). Projects that would exceed applicable CNEL standards are required to mitigate project-related noise.
Roadway traffic, construction, aircraft, events, and recreational activity can all generate noise that impacts CNEL. Natural events such as thunderstorms and wind influence noise levels as environmental drivers.
Delivering and Measuring Success
Monitoring Programs
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Noise - Plan Areas
TRPA monitors background noise levels in all Plan Areas in the Tahoe Basin to ensure noise levels are not disturbing people and wildlife, and to maintain the unique characteristics of the Basin.
Rationale Details
- At or Somewhat Better Than Target. To measure the current status, the average CNEL for all days measured within High Density Residential land use areas during the current evaluation period of 2020-2023 was used. The average CNEL during this period is 48 dB, which is 87 percent of the maximum allowable levels. Therefore, the current status is at or somewhat better than target.
- Little or No Change. To determine trend, the average CNEL for all days measured within high density residential land use areas for each reporting period is assessed. The long term trend line shows a percent change of -0.08, therefore, little or no change as occurred.
Confidence Details
- High. Noise monitoring follows monitoring protocol and has consistent data for several monitoring periods with spatial variation.
- Low. Confidence of trend is determined by the duration of trustworthy data and both the coefficient of determination and t-test significance. There is a long term trustworthy dataset for noise. R²= 0.15 (low), p-value= 0.37, therefore, the confidence of trend is low.
- Moderate. If one confidence rating is high and the other is low, the overall confidence rating is moderate.
Additional Figures and Resources
No photos available.
No documents available.