SinkholesSinkholesGeography in the NewsGeography in the News

What is a sinkhole?What is a sinkhole?

• A sinkhole is a natural depression/hole in the Earth’s surface. They vary from 1-600m in depth and diameter. They occur worldwide.

• They are naturally caused by the collapsing of a cave roof or water table roof or by the dissolving of the rock underneath the soil.

• They are artificially caused by aquifer pumping, the collapsing of mine roofs or by sewer pipes as the sewage erodes the surrounding soil or by water leaking through pavements/concrete.

How they occurHow they occur

The clay soil and limestone rock beneath the surface is, in some places, naturally acidic, as rain falls and infiltrates into the ground it becomes acidic.

Over time, the acidic water slowly erodes away the limestone. Spaces & caverns develop where the rock once was. These spaces/caverns get bigger as the limestone is eroded away., yet the surface stays in tact.

When there isn’t enough material left to support the soil above, it collapses into the spaces/caverns. Many sinkholes come unexpectedly and are unstoppable.

Case StudyCase Study

• On Sunday 11th August 2013, a sinkholeopened up under the Summer Bay Resortin Clermont Florida, aprox. 10mins fromDisneyland.

• At 10.30pm a security guard was notified of a window blowing out by a guest and when a 2nd window blew out, decided to evacuate the villa.

• After 15mins, an estimated 105 people had been evacuated from the villa including many others from surrounding buildings.

• 40mins later the whole structure came down into the sinkhole.• A crater up to 100ft/30m in diameter swallowed much of the villa and caused

another to partially sink.• Nobody suffered any injuries during the incident.• 15yrs ago, before construction, the site where the villa was built underwent

geological testing and the ground was proved to be stable.

EffectsEffects

• The villa, with 24 three-story units, was reported as a total loss.– Loss of income

– Extra costs in reconstruction

• Guests lost belongings that couldn’t be recovered.– Wallets, keys, passports, money etc.

– People would struggle to get home

ResponsesResponses

• The resort gave all affected guests new rooms.• Summer Bay gave cash advances to many guests

who had left wallets & other belongings behind.• The Red Cross also distributed food, clothing and

medicines to vacationers who had lost their belongings in their resort rooms.

• Florida received $1.08million to study the state's vulnerability to sinkholes.– Locate areas at risk of future sinkhole development

ResponsesResponses

• The resort gave all affected guests new rooms.• Summer Bay gave cash advances to many guests

who had left wallets & other belongings behind.• The Red Cross also distributed food, clothing and

medicines to vacationers who had lost their belongings in their resort rooms.

• Florida received $1.08million to study the state's vulnerability to sinkholes.– Locate areas at risk of future sinkhole development