The start of safety modification work at the Nelson Reservoir Dikes in Montana, US, is being pushed back by a year to allow the work to be completed in one season, the US Bureau of Reclamation (USBR) has announced.

The start of safety modification work at the Nelson Reservoir Dikes in Montana, US, is being pushed back by a year to allow the work to be completed in one season, the US Bureau of Reclamation (USBR) has announced.

The work will now start in the fall of 2015, rather than later this year.

"One construction season is important to minimize the required timeframes the reservoir levels will be drawn down," said Brent Esplin, Montana Area Manager. "The work will require the reservoir to be drawn down approximately 16ft lower than normal operating levels during the winter of 2015-2016.

"Interim safety measures have been implemented and frequent monitoring of the safety deficiencies are being carried out to ensure public safety until the modifications are completed," added Esplin.

Modification work is needed to allow USBR to correct seepage-related safety deficiencies for the two largest dikes at Nelson Reservoir, which is located in Phillips County.

USBR carried out an environmental assessment for the modification works and signed a Finding of No Significant Impact (FONSI).