Dam safety

Types of Dams

Understanding dam types assists tailored safety designs while recognizing failure modes enables targeted monitoring and pre-emptive action.

1. Gravity Dams utilise their substantial weight and shape to resist the lateral water pressure from the reservoir. Concrete gravity dams require careful sitting on sound bedrock and control of seepage forces.
2. Arch Dams have a curved shape that transfers water pressure into the adjacent canyon walls. This takes advantage of the natural strength of the surrounding geology. The curvature must be designed to handle varying reservoir levels. 
3. Embankment Dams rely on a large volume of earthen or rock-filled material to resist the water pressure. Proper construction of zones using filters and transitions is key to avoid erosion or sliding issues. Regular inspections monitor potential settling or movements.

Modes of Dam Failure 

1. Overtopping occurs when reservoir inflows exceed the dam’s spillway capacity, causing water to flow uncontrolled over the top of the dam. This can erode the structure and rapidly trigger complete failure. Adequate spillway design and emergency action plans are essential safeguards.
2. Structural Failures arise from defects in materials, foundations, or design flaws that lead to collapse. Earthquakes also damage dam integrity. Robust engineering guided by risk analysis minimises such threats over the project lifespan.
3. Piping refers to internal erosion from seepage forces creating channels through the dam or its foundation. Continued erosion can lead to eventual breach. Controlling seepage by drainage design and monitoring for sink holes or discolouration are preventative measures.

Other infrastructure

From roads and bridges to electrical systems, vigilance in design, construction and operation is needed.

Road and bridges

Road and bridge infrastructure constitutes the lifeblood of access for construction and later maintenance. As terrain is altered, regular inspections help identify emerging vulnerabilities to floods, landslides or structural deficiencies. Load ratings and seismic resilience should match equipment needs throughout the project lifespan as well.

Water Safety

Safety on and near water merits special emphasis for workers and the public via warnings, barriers and emergency action plans. Whether reservoirs, spillways or downstream areas, risks evolve across hydrological seasons and decades. Education and appropriate safety systems can mitigate risks.

Blasting and excavation

Blasting and excavation best practices minimise hazards from vibrations, flying debris and unintended side-effects. Strict protocols and real-time monitoring ensure foundation integrity as heavy machinery alters landscapes with little margin for error.

Electrical infrastructure

Electrical infrastructure demands proper grounding, surge protection and insulation safeguards to handle variable water flows. Safety systems should address flood inundation risks and require regular maintenance against faults during decades of operation. 

Natural hazards

Natural hazards like floods, landslides, sinkholes or extreme weather events require integrated assessments and early-warning systems. Robust designs suit heightened risks from climate change across infrastructure lifecycles measured in centuries.

Pressurised conveyances

Pressurised conveyances through dams and tunnels handle immense hydraulics, necessitating resilient materials, safety valves and vigilant monitoring. Robust construction stands up over time while allowing inspection of critical joints.

Foresight and precaution in design couple with ongoing vigilance decades later for responsible projects.

Contribution to public safety

Hydropower infrastructure also holds untapped potential for enhancing community safety against disasters like floods, droughts, and wildfires. Furthermore, the roads, bridges, and accessibility accompanying new hydroelectric projects open avenues for expanded traffic and emergency response capabilities.

Flood control can be a major motivation behind dams and their reservoirs. Excess flows can be retained and released under controlled conditions to protect populations downstream. This flood mitigation function will only grow in importance as climate change increases rainfall variability. Similarly, stored water sustains flows during drought, facilitating navigation, agriculture, and environmental needs. Reservoirs can also help suppress wildfires through maintaining moisture levels in surrounding areas when strategically tapped.

Associated infrastructure like roads and bridges built for hydropower facilities also improves regional access and evacuation capacities for first responders. New routes to remote areas aid firefighting efforts as well as ambulance services. Upgrades like safety barriers, warning signs, and lighting additionally protect local traffic. Public awareness campaigns educate communities around new hydrological patterns from the dams too, helping instil a culture of safety.

In essence, planners must move beyond just energy potential to recognise the versatility of hydropower projects supporting disaster preparedness and response. Reservoirs confer flexibility to mitigate floods and droughts alike while roads expand emergency accessibility. The compounding public safety benefits may well justify projects even absent power generation needs. With foresight and integrated planning, hydropower’s protective promise can be unleashed alongside its megawatts.