Environmental concerns: effects of underwater structures, dams & weirs, pontoons, and small hydro-electric plants

There are many underwater structures involved with power generation and water abstraction which can affect the aquatic environment; effects can be negative or positive. Bridges and pontoons can alter flow dynamics, leading to changes in erosion and deposition, but can also enhance the range of available habitat and shelter for aquatic species.

Weirs and sluices cause significant and long-lasting changes to the dynamics of waterways, leading to increased siltation upstream, and greater scour and erosion downstream, as well as forming a physical barrier to migratory species such as salmon, shad and lamprey. These issues may need to be addressed with the provision of fish ladders or passes to allow migration.

Small hydro-electric stations are generally viewed as low-impact and environmentally friendly, but they can alter flow, deposition and erosion patterns, and migrating fish (such as salmon smolts) can be liable to turbine damage if fish passes and/or a barrier system of some kind are not provided.

Pisces can provide advice and expertise on the full range of environmental and operational issues - please contact us for further information and assistance.