By early February, the heavy tephra fall had abated, but lava flows began to cause serious damage. Submarine activity just north of the fissure severed an electric power cable and a water pipeline which supplied electrical power and water from the Icelandic mainland, and lava began to flow towards the harbour, a situation which caused serious concerns - if the harbour was destroyed, the island's fishing industry would be devastated. By early May, about 300 buildings had been engulfed by lava flows or gutted by fire and 60-70 homes had been buried by tephra.(Richard & James, 1983) As Heimaey was responsible for some 3% of Iceland's GNP, the effect on the whole country's economy would be significant. Efforts to prevent the loss of the harbour are described further below.