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Carson Basin-SW 39th Stormwater Project

Construction type
Sewer and Stormwater
Project status

Environmental Services, your sewer and stormwater utility, has finished designing a project to address stormwater challenges in the SW Carson Basin. Taking these actions now will help protect public health and the Tryon Creek Watershed by reducing the possibility of flooding in your neighborhood.

Construction is scheduled to begin in April 2021 and will last until November 2021.

Project Area

What's Happening Now

Over the next few months, you may see crews locating utilities, surveying, trimming trees, setting up tree protection measures, mobilizing materials and equipment, and setting up traffic controls to prepare for construction. These activities occur over time, rather than all at once.  

We Want to Hear from You

Please let us know if you have a concern or question about the project. Be sure to include your name, property address, and project name (Carson) in your voicemail and email so we can provide you more details about what to expect in front of your property. Also, please write “Carson” in the subject line of your email.  

Environmental Services will be working with our contractor to do all we can to minimize construction impacts on the neighborhood. Construction is noisy, dusty, and causes vibration. It will be disruptive. 

Construction Methods

The contractor will use open trench excavation and horizontal directional drilling to construct the stormwater improvements.  

This project will also include the following construction elements: 

  • Construction of a 100-foot-long bioswale to capture excess stormwater. 

  • Repairing any open trench excavation section to preconstruction conditions. 

What to Expect

The contractor will develop detailed traffic control plans before construction begins. You can expect the following activities and impacts during construction: 

  • Noise, Vibration, and Dust: Construction creates noise, vibration, and dust and disrupts normal neighborhood activity. 

  • Equipment Storage: Equipment and materials may be stored on streets overnight. 

  • No Parking: Little or no on‐street parking will be allowed in and near work zones, especially during work hours. On days when crews will be working in front of your house or nearby, please plan ahead. If you park your vehicle on the street, plan to move it off the street by 7 a.m. and return it at 6 p.m. 

  • Traffic Delays: Expect traffic delays in and near the work area. 

  • Services Maintained: Sewer, water, and other utilities are expected to remain in service during construction. 

  • Garbage Pickup: Access to garbage and recycling bins for haulers will always be maintained. 

We are also aware that more residents will be home due to the COVID-19 pandemic. We are working with our contractors to ensure they provide a safe, healthy, and clean work zone throughout construction. 

Project Background

In January 2018, Environmental Services initiated a stormwater study in the Tryon Headwaters area (Tryon Creek above I-5). This work focused on identifying several public and private actions and investments to address stormwater management in the area. Environmental Services developed a plan to immediately address the simplest and most cost-effective actions first, giving more time for more research and design work on more complex solutions in the future. The Carson Basin-SW 39th Stormwater Project was identified as one of these early cost-effective projects. 

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Sign up for regular updates at Carson Basin Stormwater Project.  

What We've Heard from You

For several years, Environmental Services has been hearing about flooding issues in the area of SW 39th and SW 37th due to the lack of a stormwater system. In addition, during our investigations we learned a portion of the private stormwater pipe along SW Carson is undersized and is in poor condition. Environmental Services will replace the pipe along SW Carson as part of the project and we will take on the responsibility for long-term maintenance of the pipe within the right-of-way.