Trampers are being warned to take extra care in part of the Mt Aspiring National Park where heavy rain has been falling.
The Department of Conservation issued a ''code amber'' warning yesterday morning for the Young Valley through which the Gillespie Pass track passes.
Doc Wanaka spokeswoman Annette Grieve said the alert was issued following a MetService ''severe weather warning'' for the the valley.
''Due to the continued current heavy rain warning the department has extended the `high alert warning' for this valley.
''Trampers are being advised that if they intend to use this area during this period, not to camp in the valley floor and move through the Young Valley as quickly as possible.''
Ms Grieve said the situation would be reviewed today at 8am.
Depending on the level of rain received and the forecast at that time, ''a code red status may be activated to close access to the area as per the Young Valley management response plan, or this alert will be removed''.
The plan was Doc's response to a landslip dam formed in the Young River in September 2007, creating a lake in the north branch of the valley which is considered a potential risk to public safety in heavy rain.
On Anzac Day, American student Allison ''Ally'' Willen (20) died in the Young Valley while negotiating the flooded track.
