Authorities in the City of Riverdale in Weber County, Utah, have issued a Notice of Order to Vacate and Abandon order to the owners of three houses in the city which have been threatened by a progressive landslide, which began in November 2017, when the cliff face was more than 50 m from the buildings, and is now within four metres of one of the homes. The order requires that the owners to abandon the properties, which now can never be re-occupied, but differs from a Demolition Order, which would require the homes to be demolished, but offer the home-owners compensation for this. This difference has drawn strong criticism from members of the community, who are concerned that the owners (and any further residents that might be effected if the landslide spreads further, one other home is currently the subject of an evacuation order) are likely to be made homeless and with very heavy debts (one family have admitted to an outstanding mortgage of US$123 000 and the status of the others is likely to be little better). To this end neighbours have organised yard-sales to raise funds for the victims of the landslide, but this is unlikely to raise the sort of sums needed to remedy the situation. City administrators have said that they are 'heartened' by the efforts of neighbours to help the families, but 'irked' at criticism directed at the city.
Homes in Riverdale, Utah, threatened by a progressive landslide. Dennis Montgomery/Standard Examiner.
The landslip is thought to have been caused by water from natural springs, which has permeated through the ground to reach the cliff face. Water in sediments in such areas is dangerous as as excess pore water pressure can overcome cohesion in soil and sediments, allowing them to flow like liquids. However many residents of the area struggle to understand how this could suddenly become an issue, and suspect that water from leaking water pipes in the area may be the real culprit.
The Riverdale landslip seen from above. Riverdale City.
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