Structural Projects

Structural projects are strategies that help manage flooding by building or enhancing public infrastructure along stream corridors. Key elements include:

  • Projects scattered throughout the basin that provide benefits to affected neighborhoods

  • Typically led by public agencies

  • Limited locations are available for structural projects

TWEC technical experts reviewed an inventory of planned capital projects that are already funded to evaluate add-on opportunities. TWEC is also considering potential new structural projects and revenue sources for implementation.


CONVEYANCE: Projects that help move water downstream more quickly.

  • Promotes neighborhood drainage

  • Retrofit conveyance in existing neighborhoods

  • Consider the risk of moving flooding problems downstream


NATURAL RESOURCE ENHANCEMENT: Restoring natural areas like wetlands to absorb flood water.

  • Requires larger amounts of land relative to expected flood mitigation, though the land may be protected by existing regulations

  • Focuses on ecosystem health and long-term flood resilience

  • Intermediate cost compared to other structural projects


STORAGE/DETENTION: Projects that hold flood water in a controlled area and release it slowly.

Water storage is usually held within creek corridors, and is referred to as in-line storage.

  • Retrofit existing storage in neighborhoods

  • Explore if new storage level controls may be an option to drain water before large rain events

  • Improve local habitat as part of storage project

  • Consider difficulty to maintain fish passage with in-line storage projects


SEDIMENT REMOVAL: Projects that increase the amount of water that can be stored in streams by removing fine sand and mud that builds up over time.

  • Interrupts the natural process of landscape evolution

  • Not sustainable but may be temporarily useful for water, or sediment storage

  • Would require periodic site disturbance with ecological risks

  • Requires challenging permit processes

  • Can be costly relative to benefits