Lytle Creek Flood Protection and Habitat Preservation

San Bernardino County, CA


PACE studied the watershed and performed planning and design services of streambank protection facilities along Lytle Creek for a 3,500-home residential development located adjacent to the City of Rialto and the Lytle Creek alluvial fan floodplain. PACE is providing 7.1 miles of streambank revetment design to satisfy the project’s flood protection need and performed a sophisticated hydraulic and fluvial analysis to accommodate the challenges of alluvial fan geometry, evaluation of sensitive habitat, habitat restoration in the Sycamore Creek, in-stream existing gravel mines, large sediment delivery of cobbles and boulders and sensitive endangered species. The streambank protection utilizes a grouted rock revetment because of the dynamic nature of the floodplain and extreme hydraulic conditions. A detailed impacts assessment was performed on the floodplain to satisfy environmental resource agencies, which required extremely complex two-dimensional hydraulic models and evaluation of the influence on native vegetation within the floodplain. In addition to the streambank revetment, a gabion groin system was utilized to protect an endangered species habitat preservation area.


Key Features:

  • Complex fluvial model / scour analysis
  • Alternative facility sizing
  • Revetment feasibility study
  • Environmental hydraulic impact assessment
  • Sensitive species habitat protection
  • Gabion groin streambank stabilization
  • Revetment PS&E
  • Complex two-dimensional hydraulic modeling
  • Geomorphic investigation
  • Operation and maintenance manual
  • CLOMR processing
  • USACE 408 permit processing

Lytle Development Company

Flood Control Systems, GIS Water Resource Applications, Stormwater Management / Flood Control