Adding Water Quality Features
To achieve the EWP program ’ s goals , the team worked through summer 2021 to protect as many structures as possible at priority sites . This meant adding flood barriers and water quality features aimed at addressing three main hazards presented by the fire damage : instream erosion , roadway hazards , and hill / slope erosion , said Chelsey Heiden , Ayres ’ water resources engineer who assisted with the project .
To lessen in-stream erosion , Ayres designed and installed rock and log checks and log jams , said Will deRosset , a senior hydraulic engineer at Ayres who was instrumental in the overall mitigation efforts .
“ These features add structural diversity to the stream that ultimately reduces flow velocities and provides opportunities for sediment deposition , reducing the amount of debris that ends up in the Poudre River ,” he explained .
To decrease damage to roads at tributary streams , the team designed armored rock crossings to take the place of culverts , which get clogged with debris . The team also installed water bars , which are dips in the road that divert the channel to keep water from flowing down the road and put it back into the creek .
Finally , other consultants on the recovery team are continuing to conduct aerial mulching to alleviate erosion on hillsides . This technique involves dropping mulch from a helicopter onto the hillsides . The mulch holds moisture , helps promote vegetation growth , and provides storage for the water .
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6 | TRENDS Ingenuity , Integrity , and Intelligence .