Clear Creek Gravel Augmentations, 1996-2021

Clear Creek Anadromous Fish Habitat Restoration and
Management Project (aka “Gravel Augmentations”), 1996-2021 The purpose of the Clear Creek Gravel Augmentation Project (the
Project) is to improve habitat conditions in Lower Clear Creek for
anadromous salmonid species, including spring-run, fall-run, and
late fall-run Chinook salmon, and Central Valley steelhead. This
programmatic effort was formally titled Lower Clear Creek
Anadromous Fish Habitat Restoration and Management Project
(LCCAFHRMP), though “gravel augmentations” remains the most
commonly use name for the project. The Project is implemented
annually to improve fish habitat by placing gravel and other
desirable materials into the stream channel with the intent of
restoring and maintaining the balance of sediment in Clear Creek,
providing desirable creek channel attributes like floodplain
connectivity, channel migration, fish habitat formation (e.g.
spawning habitat), and supporting riparian community development.
The Project is proposed to meet the requirements of the CVPIA 3406
(b)(12) which has identified the lack of in-stream spawning gravel
as a significant factor limiting anadromous fish reproduction in
Clear Creek. The Clear Creek Gravel Augmentation Project consists
of adding clean (washed), size-sorted natural river gravel
directly (riffle supplementation) or indirectly (talus cone,
lateral berm) into the Clear Creek channel, along with other
desirable materials (i.e., large wood and boulders). The project
is funded by the CVPIA. Each year, the Clear Creek Technical Team
chooses the top priority gravel augmentation sites for
implementations.

克利尔溪洄游鱼类栖息地修复与管理项目（又称“砾石增补工程”），1996年—2021年
本项目旨在改善下克利尔溪的栖息环境，以服务于洄游鲑形目鱼类，包括春型、秋型及晚秋型奇努克鲑（Chinook salmon），以及中央谷钢头鳟（Central Valley steelhead）。本项目的正式全称为下克利尔溪洄游鱼类栖息地修复与管理项目（Lower Clear Creek Anadromous Fish Habitat Restoration and Management Project, LCCAFHRMP），但“砾石增补工程”仍是该项目最广为使用的名称
本计划性工作每年均会实施，通过向河道投放砾石及其他适宜物料，修复并维持克利尔溪的泥沙平衡，打造洪泛区连通性、河道迁移、鱼类栖息生境（如产卵场）等优质河道属性，并支持河岸群落发展，以此改善鱼类栖息条件
本项目的设立旨在满足中央谷项目改进法案（Central Valley Project Improvement Act, CVPIA）第3406(b)(12)条的相关要求——该法案已明确，河道内产卵砾石匮乏是限制克利尔溪洄游鱼类繁殖的关键制约因素
克利尔溪砾石增补工程主要包括向克利尔溪河道投放经清洗、分级的天然河砾石，投放方式分为直接投放（浅滩补给）与间接投放（岩屑锥、侧岸护堤）两类，同时辅以大型枯木及巨石等其他适宜物料。本项目由中央谷项目改进法案（CVPIA）提供资助
每年，克利尔溪技术团队都会选定本年度优先级最高的砾石增补作业点位。