Table 4 Volcanic ash-induced mitigation matrix (source: Daly and Wilkie, 1999 )
From: The genesis of volcanic risk assessment for the Auckland engineering lifelines project: 1996–2000
Structure | Before the event | During ashfall event | After the event |
|---|---|---|---|
Pipework | |||
Open systems (ie stormwater) | Increase awareness of potential problems, develop contingency plans | Monitor turbidity levels, where possible limit ash entering systems | Monitor turbidity levels, where possible limit ash entering systems, remove ash from pipes. |
Closed systems | N/A | N/A | N/A |
Building structures | Increase awareness of potential problems, develop contingency plans | Close windows, doors and other openings | Initiate ash removal procedures immediately, prioritize efforts |
Building services | |||
Air-conditioning | Increase awareness of potential problems, develop contingency plans | Shut down and cover air-intakes, if still in use monitor filters and clean or replace when necessary | Initiate ash removal procedures immediately, prioritize efforts |
Gutters | Increase awareness of potential problems, develop contingency plans | N/A | Remove ash to prevent loading damage |
Electricity services | Increase awareness of potential problems, develop contingency plans | ||
Power lines | Cut back tree branches from above lines | Monitor the situation carefully | Initiate ash removal procedures immediately, prioritize efforts |
Power line and substation insulators | Increase awareness of potential problems, develop contingency plans | Monitor the situation carefully | Initiate ash removal procedures immediately, prioritize efforts |
Civil structures | |||
Roads and rail | Increase awareness of potential problems, develop contingency plans | Monitor the situation carefully, limit vehicle use | Initiate ash removal procedures immediately, prioritize efforts, enhance vehicle maintenance. |
Wastewater | Increase awareness of potential problems, develop contingency plans | Warn public against disposing of ash in the stormwater system | Warn public of disposing of ash in the stormwater system. |
Sewage pumps | Increase awareness of potential problems, develop contingency plans | Monitor turbidity levels in the sewage and shut down if levels are high | Monitor turbidity levels in the sewage and shut down if levels are high. |
Sewage treatment plant | Increase awareness of potential problems, develop contingency plans | Monitor turbidity levels in the sewage and shut down if levels are high | Monitor turbidity levels in the sewage and shut down if levels are high. |
Water supply systems | Increase awareness of potential problems, develop contingency plans | Cover reservoir ventilators, disconnect roof fed supplies, monitor water quality | Initiate water supply management procedures, monitor water quality |
Telecommunications | Increase awareness of potential problems, develop contingency plans | ||
Exchange equipment: | |||
External air-conditioning | Fit internal air-conditioning units | Seal exchanges where possible, shut down if required, monitor the situation carefully | Initiate ash removal procedures immediately, prioritize efforts |
Microwave towers, other equipment | N/A | Monitor the situation carefully | Initiate ash removal procedures immediately, prioritize efforts |
Specific infrastructure | |||
Ports | Increase awareness of potential problems, develop contingency plans | Shut down vulnerability equipment, monitor the situation carefully | Initiate ash removal procedures immediately, prioritize efforts |
Airports - Air transport | Increase awareness of potential problems, develop contingency plans | Close airspace, shut down airports | Initiate ash removal procedures immediately, prioritize efforts |