Despite decades of using its creeks as dumping grounds for all kinds of waste, Charlotte has since embarked on a transformational journey towards how it values its waterways. Urban streams are often hidden under concrete, lacking native vegetation and healthy banks, and are usually heavily eroded due to being straightened or channelized. Stream restoration projects aim to re-create a stream's natural channel design, through adding bends or "meanders" that re-connect the stream to its floodplain. Bank stabilization and re-vegetation with native plants are both crucial for preventing erosion, providing shade for the creek, and creating habitat corridors for wildlife. Urban stream restoration presents many challenges, as the projects are limited by roads, property boundaries, overpasses, utility lines, and other urban infrastructure (Angione, 2007). These projects often cost millions of dollars and can take several years to observe results. Not only do stream restoration projects improve water quality and restore critical ecosystem services, but they can also generate incredible recreational, aesthetic, and economic value for cities. Because of its polluted past and high visibility running through most of Charlotte, Little Sugar Creek has been the focus of many restoration efforts over the years.
A restored meander along Little Sugar Creek | Image credit: Cecilia Kammire
Stream restoration projects also aim to create better in-stream habitat, which can be achieved through flow diversity, such as having riffles, pools, and runs as shown in the diagram below. As a result of stormwater runoff scouring the bottom of urban streams, many have wide channels with a primarily sandy bottom, which fails to provide necessary habitat for aquatic and benthic organisms. Riffles, runs, and pools can create macro-habitats, while rocks leaf litter, and woody debris can provide microhabitats for smaller organisms (Fuller, 2018). Riparian vegetation not only stabilizes banks, but also provides shade for the creek, habitat, and leaf litter provides food for benthic invertebrates. The presence of benthic organisms and healthy fish populations are often good indicators of water quality, as they are vital components of a healthy watershed.
Elements of a natural stream reach: pool, riffle, and run | Image source: Arizona Geological Survey Contributed Report (Fuller, 2018)
Slides showing restored stream channel features along Little Sugar Creek | Images Credit: Cecilia Kammire
Little Sugar Creek Greenway
In the 1990s, the landscape architectural firm Land Design partnered with Mecklenburg County to reimagine the way the city viewed Little Sugar Creek- transforming it from a polluted eyesore to an urban recreational oasis through designing a greenway. They approached this massive undertaking through addressing the physical, functional, and social qualities of the creek.
In 2002 the concrete cap (that was placed over the creek for the former Charlottetown Mall parking lot) was removed around Midtown. Major stream enhancements began and through restoring the creek banks and planting native vegetation, wildlife began to slowly return. Although this project improved the water quality and celebrates the creek, Little Sugar still carries pollutants as an urban creek, so pedestrian bridges were created to keep people out of the water. This initiative inspired other greenway projects throughout Mecklenburg County, which aim to restore natural stream features and connect people with local urban wildlife. This video on Land Design’s project website provides an educational description of the undertaking, with shocking before and after photos.
Now completed, the Little Sugar Creek Greenway runs almost 19 miles, starting in North Charlotte and running all the way down to the NC/ SC state line. My ongoing photo gallery in a separate post reveals some of the wildlife that can be spotted along the Greenway.
Little Sugar Creek Greenway | Image Credit: Cecilia Kammire
Stream Buffers
To mitigate Charlotte’s major issue with historic stream bank erosion, stream buffer ordinances are enforced to ensure streams can fulfill their natural ecological functions. Charlotte- Mecklenburg contains 4 different types of stream and lake buffers, which vary based on local ordinance requirements and jurisdiction where they are located. Stream buffers are vegetated areas spanning a certain distance on both sides of the stream channel that allow the stream to meander naturally. Buffers create numerous ecosystem services and improve water quality by filtering pollutants, absorbing runoff, creating habitat for wildlife, and providing soil stability through root mass.
A steam buffer sign near Freedom Park | Image Credit: Cecilia Kammire
Wetland Creation
Between 2003 and 2016, Charlotte-Mecklenburg Storm Water Services (CMSWS) improved and restored nearly 30 miles of stream and 18 acres of wetlands. Completed in 2004, the Hidden Valley Ecological Garden project is located in the Hidden Valley neighborhood near Little Sugar Creek's headwaters. The project involved re-meandering over 2,000 linear feet of the previously channelized and eroded stream. A series of floodplain riparian wetlands were created using a natural systems approach. Riparian and wetland revegetation involved soil bioengineering and the use of native trees, shrubs, and ground cover plants. This project marked the first creation of an urban wetland/ water quality basin in North Carolina (Wildlands Engineering).
Also in 2004, the City of Charlotte created a Stream and Wetland Mitigation Bank, that essentially generates “mitigation credits” whenever CMSWS performs stream enhancement or restoration projects within the county. City or County agencies can buy these credits to offset the environmental impacts caused by new construction projects. Those funds go back towards the Mitigation Bank and fund further restoration initiatives, ensuring that mitigation efforts remain localized in the county near the actual infrastructure projects. One successful project the Mitigation Bank funded was the Edwards Branch Watershed Improvement Project. Completed between 2001- 2015, this project restored nearly 7,000 linear feet of the stream, in addition to constructing wetlands, a wet pond, storm water swales, and buffer enhancements.
Charlotte- Mecklenburg Stormwater Services is currently performing stream and wetland restoration along Little Sugar Creek from I-485 to the South Carolina State Line to improve water quality and reduce erosion. Their official website shows more than 50 ongoing storm drainage improvement and restoration projects.
Sources:
Angione, K. (2007, November). Cracking the Culvert: Urban Stream Restoration in North Carolina. Coastwatch. https://ncseagrant.ncsu.edu/coastwatch/previous-issues/2007-2/holiday-2007/cracking-the-culvert-urban-stream-restoration-in-north-carolina/
City of Charlotte, Storm Water Services: https://www.charlottenc.gov/Services/Stormwater/Surface-Water-Quality/Monitoring#WI
Fuller, J.E. (2018). Defining Ordinary and Natural Conditions for State Navigability Determinations. Arizona Geological Survey Contributed Report CR-18-B, 135p. https://www.researchgate.net/publication/322765638_Defining_Ordinary_and_Natural_Conditions_for_State_Navigability_Determinations?enrichId=rgreq-7614614ec5636c745893a7c8c6fbef80-XXX&enrichSource=Y292ZXJQYWdlOzMyMjc2NTYzODtBUzo1ODgxNTQ0NzQwNzgyMDhAMTUxNzIzODM2MjM2NA%3D%3D&el=1_x_2&_esc=publicationCoverPdf
Land Design, Little Sugar Creek Greenway: https://landdesign.com/project/little-sugar-creek-greenway/
Wildlands Engineering, Briar Creek/ Edwards Branch Stream Restoration Project:
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