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Abstract: Session B  9:20 am (Back to Session B)
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Katy Prairie Stream Restoration: An Illustrative Use of Stream Restoration to Create Resilient Ecosystems

George Athanasakes
Stantec Consulting Services Inc
Louisville, KY

The geomorphic approach to stream restoration was recently applied on a large scale in Katy, Texas immediately northwest of Houston on land managed by the Katy Prairie Conservancy as part of a stream mitigation bank.  This project included reconstruction of over 18 miles of stream restoration along eight reaches of stream.  Goals of this project were to correct overall stream function by addressing the fundamental processes of channel incision and bank erosion driving instability.  Secondary effects included reestablishment of wetlands along the riparian corridor to improve water quality, enhance flood attenuation and expand near-stream habitat; re-introduction of wood into the channel to increase in-stream habitat and support the creation of perennial pools in an intermittent stream; and systemic improvements to the landscape to provide compensatory mitigation credits. 

Natural channel design techniques were utilized to restore the streams at Katy Prairie.  The design included consultation of reference reach parameters coupled with sediment transport analyses to design a stable, self-maintaining stream system.  The design for the project focused on restoring floodplain access by reconnecting the stream to the floodplain, re-distributing energy throughout the cross section, and providing grade control to prevent future channel incision.  The design also focused on re-establishing habitat within the channel and throughout the adjacent floodplain by re-creating kettle wetland features. 

The resiliency of this site was recently tested during Hurricane Harvey.  It is estimated that the hurricane produced an approximate 500-year flow event near the site.  Results of monitoring indicate that the site withstood the event with minimal evidence of erosion or other indicators of instability.  This talk will discuss the design of stream restoration to promote resilient ecosystems and will present the design approach and results of monitoring for the Katy Prairie project.