This is a bit on disasters I wrote up not too long ago, made mostly from ideas I've over the last few years and inspired by various actual disasters. The Hurricane was inspired by actual hurricanes but also the devastation from Hurricane Harvey, which dumped an enormous amount of rain in Houston. The buckling infrastructure is real--water sat in a depressed freeway for weeks and when it was drained, some of the pavement had buckled and broken, making it unusable until crews were able to replace and patch in new concrete. The riots were from reading about Detroit in the 1960s and how whole blocks burned up because the fire department was not able to reach them. The Industrial Explosion was based after the incident in West, Texas in 2013.
Fires
Triggers: Menu, random event by simulation variables
Nuisance Value: Mild to Catastrophic
Conditions: Like SimCity 2000, fires are random occurrences with modified variables, like dry season, their flammability value, and fire coverage.
Countermeasures: Well-funded fire stations can prevent fires from spreading.
Description: The fire has multiple phases that may or may not destroy an entire building. Sending firefighters to the scene can help prevent it from spreading, because it can spread during wind. They spread pretty fast. Most of the disasters either start with fire or start fires.
Flood
Triggers: Menu, random event by simulation variables
Nuisance Value: Mild to Serious
Conditions: Most likely in the wet season
Countermeasures: Detention ponds and dikes usually help.
Description: Water will rise at the lowest elevation, causing abandonment and destruction. How much is random. See hurricane.
Hurricane
Triggers: Random event
Nuisance Value: Mild to Catastrophic
Conditions: High winds and a coastline.
Countermeasures: Same as floods, detention ponds and dikes can mitigate damage.
Description: Hurricanes you WILL get a warning for. Sometimes it's going to be relatively mild and you'll just have high winds and a lot of rain but ultimately not much damage, if you're lucky. A hurricane won't destroy everything in its path like fires will, but they tend to affect infrastructure a lot more. Pipes will break, and highways, roads, and bridges will buckle or be washed out.
Tornado
Triggers: Menu, random event by simulation variables
Nuisance Value: Mild to Moderate
Conditions: Random event by simulation variables, usually on large, flat areas
Countermeasures: Nothing much, just be prepared to rebuild.
Description: A tornado will tear through an area, destroying almost everything in its path. It may also cause fires.
Earthquake
Triggers: Menu, random event
Nuisance Value: Moderate to Catastrophic
Conditions: Random.
Countermeasures: There is an 80% chance you'll be warned ahead of time.
Description: The screen shakes and a number of buildings and infrastructure will collapse. Fires start at random places due to burst gas pipes. There's a 15% chance riots will start afterward but they're fairly mild.
Riots (Civil Unrest)
Triggers: Menu, random event
Nuisance Value: Mild to Serious
Conditions: High heat, high unemployment, high crime.
Countermeasures: Don't let "hot spots" develop.
Description: Riots are bad news and worse than SimCity 2000. You'll be alerted if a protest gets ugly but if the conditions are right, then they'll spawn in other places. Once the action starts, creepy music will start, and they'll set fires to any buildings. You won't be able to save them, as a "no-go" area will be created as long as the riot continues. If the police can push them back enough then you might be able to save buildings. If it gets bad enough, the military will be called in and the rioters will surrender after lethal force is used. However, the affected parts of the city are in ruins. Tanks also cause a lot of road damage. Population will move out, and demand for RCI craters.
Industrial Explosion
Triggers: Fire in progress at plant with a high "explosivity" rate
Nuisance Value: Moderate
Conditions: See Triggers
Countermeasures: Keep industries that can explode away from development.
Description: An incredibly loud noise that decimates the plant on fire and creates a massive shockwave like an earthquake complete with fires. Luckily, there's no riots afterward.
Chemical Spill
Triggers: Random event modified by simulation conditions
Nuisance Value: Mild.
Conditions: Presence of lots of polluting industries.
Countermeasures: The more pollution in the city, the greater chance of one happening but otherwise not much to do. Fire departments can keep the smoke clouds back.
Description: Unlike SimCity 2000, the toxic cloud created by the chemical spill doesn't move around town, and will often hang around in one place unless there's a particularly strong wind. Every tree in the way is destroyed and water polluted. After a while, they'll dissipate on their own. This often involves evacuation, so keep the roads clear. I'm certain that the chemical spill disaster was inspired by an incident in Houston in the 1970s, where a cloud of anhydrous ammonia was created when a truck fell off an overpass and a massive cloud moved through a part of town, destroying vegetation and causing chemical burns to anyone unfortunate to be in its path.
Nuclear Meltdown
Triggers: Random event modified by simulation conditions
Nuisance Value: Serious
Conditions: A poorly-funded nuclear power plant and a roll of the dice. There's a chance that a severe flood or a big enough existing fire could damage it (as a nuclear power plant's flammability is extremely low).
Countermeasures: Fund your nuclear power plant correctly and it won't happen under normal circumstances.
Description: The nuclear power plant catches fire and permanently contaminates the surrounding area with nuclear waste, making it completely useless for anything.
KAIJU!!
Triggers: Menu only.
Nuisance Value: Moderate to Catastrophic
Conditions: Has to be above a certain population and pollution level.
Countermeasures: Unless you want to keep the city small, nothing you can do except fight it off.
Effect: A monster will tear through your city. The military will help out usually.
Train Derailment
Triggers: Random event modified by simulation conditions, tornado
Nuisance Value: Mild (usually) to Catastrophic
Conditions: Presence of a railroad in town. The more railroads the higher chance of a disaster.
Countermeasures: Keeping things away from rail can minimize damage.
Effect: The train derailment is an incident where a train can derail, damaging everything near the sides of the tracks, and unlike in SimCity 4 this isn't limited to sharp curves. When a train derails, everything around it is suspect to damage, including bridges and other structures. There's a chance (though not always) that it will have chemicals that require evacuation, and then the Chemical Spill activates. If you're particularly unlucky, it will have the effect of an Industrial Explosion and a massive fire will start.
Terrorism
Triggers: Random.
Nuisance Value: Medium.
Conditions: Must have a very high population.
Countermeasures: A well-funded police department.
Effect: A terrorist will plant a bomb which will go off in a highly-populated area. In addition to the actual damage, it will cause some significant economic issues. However, there's a good chance that your police can catch it and foil the plot.
Drought
Triggers: Random event every 50 or so years
Nuisance Value: Mild
Conditions: Nothing, it's random
Countermeasures: Nothing you can do.
Effect: The drought is a rare non-disaster thing that can happen to your city. Inspired after the 2011 Texas drought, the drought adds a challenge to your city. It's not anything to immediately fight but can cause other disasters to happen. First, it's hot, always hot, and that will give a greater chance of riots to happen. Secondly, the drought will cause people to not hang out at outdoor restaurants and bars, hurting commerce and in effect the economy. Thirdly, trees and plants will die. Fourthly, flammability of EVERYTHING goes way up, so keep that fire station well-funded. Fifthly, your water bill goes up, your citizens will pay for it but so will you.
Detectable disasters (earthquakes, hurricanes, tornadoes) will be able to allow the Mayor to select an option to Evacuate the City. At that point, the Cims will head for the doors, whether it be highway or inter-city mass transit. All lanes but one turn contraflow, so the wider the highway the better. Depending on the way your city is built, it may take a while for the city to evacuate. Do it too early (say if it's a false alarm) and your approval rating takes a massive hit. Do it too late (while people are still on the streets) and your approval rating takes a slight hit. Do it right, and enjoy a better approval rating as well as an extra bonus.
While we're on the subject, SimCity 4 did away with random disasters and put them all in "God Mode". While this prevented the random earthquake to ruin someone's day, it did take away a lot of the challenge of something like a tornado or something coming. Since no city has tornadoes, earthquakes, and hurricanes happening at ANY given chance, one should be able to change those variables before a city starts (kept in a config file). Houston may have hurricanes but not earthquakes (unless the world is ending), while Dallas has earthquakes (very minor) and tornadoes, but never hurricanes. The SimCity 4 disasters ended up being pretty weak, with THREE of them being variations of the monster (UFOs, Autosaurus Wrecks, Robot Attack), Meteor being very minor, and Lightning as pretty much a non-disaster for show.
Fires
Triggers: Menu, random event by simulation variables
Nuisance Value: Mild to Catastrophic
Conditions: Like SimCity 2000, fires are random occurrences with modified variables, like dry season, their flammability value, and fire coverage.
Countermeasures: Well-funded fire stations can prevent fires from spreading.
Description: The fire has multiple phases that may or may not destroy an entire building. Sending firefighters to the scene can help prevent it from spreading, because it can spread during wind. They spread pretty fast. Most of the disasters either start with fire or start fires.
Flood
Triggers: Menu, random event by simulation variables
Nuisance Value: Mild to Serious
Conditions: Most likely in the wet season
Countermeasures: Detention ponds and dikes usually help.
Description: Water will rise at the lowest elevation, causing abandonment and destruction. How much is random. See hurricane.
Hurricane
Triggers: Random event
Nuisance Value: Mild to Catastrophic
Conditions: High winds and a coastline.
Countermeasures: Same as floods, detention ponds and dikes can mitigate damage.
Description: Hurricanes you WILL get a warning for. Sometimes it's going to be relatively mild and you'll just have high winds and a lot of rain but ultimately not much damage, if you're lucky. A hurricane won't destroy everything in its path like fires will, but they tend to affect infrastructure a lot more. Pipes will break, and highways, roads, and bridges will buckle or be washed out.
Tornado
Triggers: Menu, random event by simulation variables
Nuisance Value: Mild to Moderate
Conditions: Random event by simulation variables, usually on large, flat areas
Countermeasures: Nothing much, just be prepared to rebuild.
Description: A tornado will tear through an area, destroying almost everything in its path. It may also cause fires.
Earthquake
Triggers: Menu, random event
Nuisance Value: Moderate to Catastrophic
Conditions: Random.
Countermeasures: There is an 80% chance you'll be warned ahead of time.
Description: The screen shakes and a number of buildings and infrastructure will collapse. Fires start at random places due to burst gas pipes. There's a 15% chance riots will start afterward but they're fairly mild.
Riots (Civil Unrest)
Triggers: Menu, random event
Nuisance Value: Mild to Serious
Conditions: High heat, high unemployment, high crime.
Countermeasures: Don't let "hot spots" develop.
Description: Riots are bad news and worse than SimCity 2000. You'll be alerted if a protest gets ugly but if the conditions are right, then they'll spawn in other places. Once the action starts, creepy music will start, and they'll set fires to any buildings. You won't be able to save them, as a "no-go" area will be created as long as the riot continues. If the police can push them back enough then you might be able to save buildings. If it gets bad enough, the military will be called in and the rioters will surrender after lethal force is used. However, the affected parts of the city are in ruins. Tanks also cause a lot of road damage. Population will move out, and demand for RCI craters.
Industrial Explosion
Triggers: Fire in progress at plant with a high "explosivity" rate
Nuisance Value: Moderate
Conditions: See Triggers
Countermeasures: Keep industries that can explode away from development.
Description: An incredibly loud noise that decimates the plant on fire and creates a massive shockwave like an earthquake complete with fires. Luckily, there's no riots afterward.
Chemical Spill
Triggers: Random event modified by simulation conditions
Nuisance Value: Mild.
Conditions: Presence of lots of polluting industries.
Countermeasures: The more pollution in the city, the greater chance of one happening but otherwise not much to do. Fire departments can keep the smoke clouds back.
Description: Unlike SimCity 2000, the toxic cloud created by the chemical spill doesn't move around town, and will often hang around in one place unless there's a particularly strong wind. Every tree in the way is destroyed and water polluted. After a while, they'll dissipate on their own. This often involves evacuation, so keep the roads clear. I'm certain that the chemical spill disaster was inspired by an incident in Houston in the 1970s, where a cloud of anhydrous ammonia was created when a truck fell off an overpass and a massive cloud moved through a part of town, destroying vegetation and causing chemical burns to anyone unfortunate to be in its path.
Nuclear Meltdown
Triggers: Random event modified by simulation conditions
Nuisance Value: Serious
Conditions: A poorly-funded nuclear power plant and a roll of the dice. There's a chance that a severe flood or a big enough existing fire could damage it (as a nuclear power plant's flammability is extremely low).
Countermeasures: Fund your nuclear power plant correctly and it won't happen under normal circumstances.
Description: The nuclear power plant catches fire and permanently contaminates the surrounding area with nuclear waste, making it completely useless for anything.
KAIJU!!
Triggers: Menu only.
Nuisance Value: Moderate to Catastrophic
Conditions: Has to be above a certain population and pollution level.
Countermeasures: Unless you want to keep the city small, nothing you can do except fight it off.
Effect: A monster will tear through your city. The military will help out usually.
Train Derailment
Triggers: Random event modified by simulation conditions, tornado
Nuisance Value: Mild (usually) to Catastrophic
Conditions: Presence of a railroad in town. The more railroads the higher chance of a disaster.
Countermeasures: Keeping things away from rail can minimize damage.
Effect: The train derailment is an incident where a train can derail, damaging everything near the sides of the tracks, and unlike in SimCity 4 this isn't limited to sharp curves. When a train derails, everything around it is suspect to damage, including bridges and other structures. There's a chance (though not always) that it will have chemicals that require evacuation, and then the Chemical Spill activates. If you're particularly unlucky, it will have the effect of an Industrial Explosion and a massive fire will start.
Terrorism
Triggers: Random.
Nuisance Value: Medium.
Conditions: Must have a very high population.
Countermeasures: A well-funded police department.
Effect: A terrorist will plant a bomb which will go off in a highly-populated area. In addition to the actual damage, it will cause some significant economic issues. However, there's a good chance that your police can catch it and foil the plot.
Drought
Triggers: Random event every 50 or so years
Nuisance Value: Mild
Conditions: Nothing, it's random
Countermeasures: Nothing you can do.
Effect: The drought is a rare non-disaster thing that can happen to your city. Inspired after the 2011 Texas drought, the drought adds a challenge to your city. It's not anything to immediately fight but can cause other disasters to happen. First, it's hot, always hot, and that will give a greater chance of riots to happen. Secondly, the drought will cause people to not hang out at outdoor restaurants and bars, hurting commerce and in effect the economy. Thirdly, trees and plants will die. Fourthly, flammability of EVERYTHING goes way up, so keep that fire station well-funded. Fifthly, your water bill goes up, your citizens will pay for it but so will you.
Detectable disasters (earthquakes, hurricanes, tornadoes) will be able to allow the Mayor to select an option to Evacuate the City. At that point, the Cims will head for the doors, whether it be highway or inter-city mass transit. All lanes but one turn contraflow, so the wider the highway the better. Depending on the way your city is built, it may take a while for the city to evacuate. Do it too early (say if it's a false alarm) and your approval rating takes a massive hit. Do it too late (while people are still on the streets) and your approval rating takes a slight hit. Do it right, and enjoy a better approval rating as well as an extra bonus.
While we're on the subject, SimCity 4 did away with random disasters and put them all in "God Mode". While this prevented the random earthquake to ruin someone's day, it did take away a lot of the challenge of something like a tornado or something coming. Since no city has tornadoes, earthquakes, and hurricanes happening at ANY given chance, one should be able to change those variables before a city starts (kept in a config file). Houston may have hurricanes but not earthquakes (unless the world is ending), while Dallas has earthquakes (very minor) and tornadoes, but never hurricanes. The SimCity 4 disasters ended up being pretty weak, with THREE of them being variations of the monster (UFOs, Autosaurus Wrecks, Robot Attack), Meteor being very minor, and Lightning as pretty much a non-disaster for show.
