The National Building Research Organisation (NBRO) has issued landslide early warnings covering several divisional secretariat areas in four districts, following heavy rain over the preceding 24 hours.

The warnings took effect at 11.00 p.m. on Sunday, August 2, and run for 24 hours until 11.00 p.m. on Monday, August 3.

Level 2 — Alert (Amber)

Second-level warnings, the higher of the two tiers issued, apply to:

Level 1 — Watch (Yellow)

First-level warnings apply to:

What residents are being told to watch for

The NBRO advised people living in hilly areas and on slopes within the listed divisions to be especially alert to sudden changes in the ground — subsidence, earth mounds cracking or heaving, and spring water turning muddy. Anyone who observes such signs has been asked to move to a safe location immediately.

A weekend of sustained rain in the hills

The warnings follow several days of heavy rainfall over the central highlands and the south-west. On Saturday the Mahaweli burst its banks at Peradeniya and Nawalapitiya, submerging a bridge repair site and flooding sixteen houses. On Sunday two spill gates at the Polgolla dam were opened, releasing 3,940 cubic feet of water per second into the Victoria Reservoir, while the Irrigation Department maintained a minor flood warning for the Kelani valley.

The Met Department’s Sunday forecast had put falls of about 50 mm at some places in Sabaragamuwa and in the Kandy, Nuwara Eliya, Kalutara, Galle and Matara districts — broadly the same catchments now under landslide warning. Separately, a red warning for strong winds remains in force for sea areas off the southern and eastern coasts.

Several of the divisions named are in terrain with a history of slope failure. Aranayake, now under a first-level watch, was the site of Sri Lanka’s deadliest landslide in recent memory in May 2016.

Update (August 3): warnings escalated twice to ‘Red’ evacuation level

The NBRO raised its alert level twice during Monday morning as rain continued over the central hills, moving from the second-level alerts issued on Sunday night to third-level evacuation warnings.

9.00 a.m. bulletin. The NBRO issued a Level 3 “Evacuation” warning for the Pasbage Korale and Ganga Ihala Korale divisions in the Kandy district, valid for 24 hours until 9.00 a.m. on Tuesday, the Daily Mirror reported. Level 2 amber warnings covered Ududumbara and Udapalatha in Kandy; Yatiyantota and Aranayaka in Kegalle; Nuwara Eliya, Norwood, Ambagamuwa Korale, Kotmale West and Kotmale East in Nuwara Eliya; and Opanayake, Imbulpe and Ratnapura in the Ratnapura district. Level 1 yellow warnings applied to Panwila and Medadumbara in Kandy, Dehiowita and Deraniyagala in Kegalle, and Nivitigala and Kuruwita in Ratnapura.

12.00 noon bulletin. Three hours later the NBRO widened the Red warning from two divisions to six, across three districts, Ada Derana reported. Red evacuation warnings now cover:

That bulletin is valid for 24 hours, from 12.00 noon on Monday until 12.00 noon on Tuesday. Level 2 amber warnings were issued for Doluwa, Udapalatha, Delthota, Medadumbara and Panvila in Kandy; Deraniyagala, Bulathkohupitiya, Aranayake and Dehiowita in Kegalle; Kotmale East, Kotmale West and Nuwara Eliya in the Nuwara Eliya district; and Opanayake, Ratnapura and Imbulpe in Ratnapura. Level 1 watches apply to Kegalle, to Hanguranketha in Nuwara Eliya, and to Kuruwita and Nivithigala in Ratnapura.

Yatiyantota, Ambagamuwa and Norwood have moved from amber to red within 13 hours. All three sit in the belt that recorded the island’s heaviest rainfall overnight: 204 mm at Watawala and 187.8 mm at Norton, both in the Nuwara Eliya district, in the 24 hours to 6.00 a.m. Monday.

A Level 3 warning is the point at which the NBRO asks residents to leave rather than watch. The organisation urged people in the affected areas to take immediate safety measures if signs of a landslide appear or if heavy rain continues, and said rainfall is expected to persist over the coming days.

The escalation runs alongside a parallel escalation on the rivers. The Irrigation Department upgraded its Mahaweli warning to a Red major-flood alert covering ten divisions at 1.00 p.m. on Monday, and roads across the hill country have been closed by rockfalls, earth slips and floodwater.