No Existing Stormwater Infrastructure
• The 441 Post Road property currently has no formal stormwater management system other than traditional catch basins and piping, resulting in unmanaged runoff that contributes to localized flooding and introduces pollutants into the adjacent Turney Creek marsh system.
The Importance of Water Quality Treatment Over Detention
• Direct Discharge Benefits:
• In tidal areas, like Turney Creek, detention systems delay stormwater release, increasing the risk of overlap with high tides and backflow.
• Direct discharge rapidly evacuates treated stormwater, preventing prolonged water retention that could amplify flooding risks.
• Advanced Water Quality Treatment:
• Systems like hydrodynamic separators and biofiltration units remove pollutants (sediments, oils, nutrients) before water is discharged.
• This ensures compliance with Connecticut DEEP standards, improving water quality in Turney Creek and protecting its sensitive marsh ecosystem.
• Flood Resilience:
• By avoiding detention, the system reduces the potential for tidal backflow, which can compromise traditional detention basins in coastal areas.
• The design aligns with CT DEEP Stormwater Guidelines, which recommend direct discharge in tidal zones to minimize interaction with tidal surges.
• Environmental and Long-Term Benefits:
• Cleaner runoff entering Turney Creek supports healthier wetlands and aquatic habitats.
• This strategy is resilient to future climate challenges, such as rising sea levels and more frequent storm events.
• The stormwater management strategy for 441 Post Road has been carefully designed to address the specific challenges of coastal watersheds like Turney Creek. By prioritizing direct discharge with advanced water quality treatment systems, the approach ensures effective flood risk mitigation while safeguarding the surrounding environment.
• In tidal zones, detention systems, which are typically used to slow the release of stormwater, pose significant challenges. When water release is delayed, it often coincides with high tide, increasing the risk of tidal backflow and localized flooding. At Turney Creek, these risks are further heightened by its sensitive tidal dynamics. Direct discharge, on the other hand, ensures that stormwater exits the site quickly, reducing the likelihood of prolonged retention that could overlap with tidal peaks.
• To complement this rapid discharge approach, advanced water quality treatment systems have been incorporated. These systems, including hydrodynamic separators and biofiltration units, effectively remove sediments, oils, and nutrients from stormwater before it is released into Turney Creek. This design ensures compliance with Connecticut DEEP stormwater standards while protecting the sensitive marsh ecosystem. By filtering pollutants at the source, the project improves the overall health of the watershed and supports local wildlife.
• The system also addresses flood resilience. By eliminating the delays caused by detention systems, the design reduces the potential for tidal backflow, which is a frequent issue in coastal areas. Additionally, this strategy aligns with Connecticut DEEP stormwater guidelines, which recommend direct discharge for tidal zones to minimize the risks associated with prolonged stormwater retention.
• The benefits of this approach extend beyond the property itself. Neighboring areas will see reduced flood risks due to the controlled and timely release of stormwater. At the same time, Turney Creek and its surrounding marshland will benefit from cleaner water entering the ecosystem, helping to maintain its delicate balance.
The 100-Year Flood Line Concern Clarification on System Placement:
• The drainage system is not installed beneath the 100-year flood line. Its placement above this line ensures it is not compromised during significant flood events and maintains operational integrity during extreme conditions.
• Coastal design standards prioritize keeping infrastructure above tidal and flood elevations for resiliency.
• Why Direct Discharge Works:
• By avoiding prolonged retention of water on-site, the system minimizes potential interactions with tidal surges or extreme flooding events.
• The drainage system for 441 Post Road has been carefully placed above the 100-year flood line. This strategic placement ensures the system is not compromised during significant flood events and maintains full operational integrity even under extreme conditions. Coastal design standards emphasize the importance of locating stormwater infrastructure above tidal and flood elevations to enhance resilience and reliability in flood-prone areas.
• The use of direct discharge complements this design by eliminating prolonged water retention on-site. This approach minimizes the potential for interactions with tidal surges or extreme flooding events, ensuring stormwater exits the site promptly and reduces the risks associated with tidal backflow or inundation.
Long-Term Benefits for Neighboring Properties
• Flood Risk Reduction:
• The controlled release of treated stormwater lowers the likelihood of uncontrolled runoff reaching adjacent properties.
• Neighboring properties benefit from reduced flood pressure and pollutant loads, particularly during heavy rainfall events.
• Ecosystem Protection:
• Cleaner runoff entering Turney Creek supports healthier wetland ecosystems, improving water quality and reducing sedimentation impacts on tidal channels.
• The stormwater management improvements at 441 Post Road provide substantial benefits for neighboring properties. Through the controlled release of treated stormwater, the likelihood of uncontrolled runoff impacting adjacent properties is significantly reduced. During heavy rainfall events, the system effectively manages flow, reducing flood pressures and protecting surrounding areas from potential overflow.
• In addition to mitigating flood risks, the improved stormwater system enhances ecosystem health. Treated runoff entering Turney Creek is cleaner and free from harmful pollutants, such as sediments, nutrients, and hydrocarbons. This cleaner water supports healthier wetland ecosystems, improves overall water quality, and reduces sedimentation in tidal channels. The resulting ecological benefits extend beyond the property itself, contributing to the long-term health and resilience of the Turney Creek watershed.