BIA Airport (Katunayake) to Hatton

NBRI’s advice, as issued ›

Heavy rain, up to 100.5 mm in 24 h

Rain gauges near your route

• 1 Katunayake, 0.8 mm, dry
• 3 Hanwella, 3 mm, light rain
• 9 Dehiowita, 89 mm, fairly heavy rain
• 12 Pambegama Tea Factory, 100.5 mm, heavy rain
• 15 Kithulgala, ≥ 52 mm, fairly heavy rain or more (incomplete day)
• 19 Norton, 90 mm, fairly heavy rain

15 gauges not reporting.

Gauge coverage: most of the route.

NBRI's warning stays in force after rain eases.

Satellite estimate

• Last 3 days: among the wettest 1% of 3-day periods since 2000 in Dehiovita.

Amber · Thunderstorms Amber Warning (Be Prepared)

• Amber · Thunderstorms Amber Warning (Be Prepared). Districts: Ampara, Badulla, Batticaloa, Colombo, Galle, Gampaha, Hambantota, Jaffna, Kalutara, Kandy, Kegalle, Kilinochchi, Mannar, Matale, Matara, Moneragala, Mullaitivu, Nuwara Eliya, Polonnaruwa, Ratnapura, Trincomalee, Vavuniya. Warning Description: There is an increased likelihood of severe lightning associated with thundershowers at several places in the following areas during the evening or night. Heavy falls above 100mm are likely at some places in Western, Sabaragamuwa, Central and Uva provinces and in Galle and Matara districts. Strong gusty winds of 60–70 kmph and very rough sea conditions can be expected temporarily during thundershowers in the sea areas. Action Required: • Stop paddy and plantation work, outdoor sports and construction when storms approach. • Move into a substantial building or an enclosed hard-topped vehicle; do not shelter under trees, open huts, tents or bus halts. • Avoid open fields, hilltops, beaches, tanks, rivers and other water bodies. • Fishermen and small-boat operators should not go to sea and should return to shore early. • Avoid bathing, using wired phones and handling electrical appliances during thunder. • Avoid travelling on tree-lined roads and through flooded roads. • Follow flood warnings and landslide warnings. • Protect livestock, crops and property, and be ready to move to a safe shelter if advised. Damage Expected: • Widespread thunderstorms with frequent lightning, strong gusty winds and heavy rain. • Risk of injury or death for people in open areas such as paddy fields, plantations, playgrounds, beaches, and for people on boats. • Trees uprooted and damage to roofs of non-engineered houses, including tin and thatched roofs. • Localized flash floods and slope failures in vulnerable areas. • Power and communication interruptions and damage to electrical equipment. • Damage to crops, plantations and livestock. • Dangerous conditions for small fishing boats and craft. • Disruption to road, rail and air transport. Issued 10 Nov, 12:45 · Valid until 11 Nov, 01:00.
• Forecast issued 10 Nov, 05:30
• Showers or thundershowers will occur at times in the Northern province and in Trincomalee district.
• Showers or thundershowers will occur elsewhere in the island after 1.00 p.m.
• Covers Kegalle, Nuwara Eliya, Colombo and Gampaha on this road: Heavy falls above 100mm are likely at some places in Western, Sabaragamuwa, Central and Uva provinces and in Galle and Matara districts.
• Showers may occur in the coastal areas of the Southern Province during the morning.
• The general public is kindly requested to take adequate precautions to minimize damage caused by temporary localized strong winds and lightning during thundershowers.
• Covers Kegalle, Nuwara Eliya, Colombo and Gampaha on this road: Misty conditions can be expected at some places in Western, Sabaragamuwa, Central and Uva provinces and in Galle, Matara and Kurunegala districts during the early hours of the morning.
• A forecast never lowers or replaces the NBRI landslide warning above.
• Forecast and advisories by the Department of Meteorology, Sri Lanka, as issued. LankaWatch is not an official service.

Crosses 13 named rivers · 3 basins · Kelani Ganga basin rain: Rare here (1–2 days a month) · rain upstream of Kelani Ganga: Rare here (1–2 days a month)

Attanagala Oya · Kelani Ganga · Mahaweli Ganga

River basins along this road

• km 0–12 · Attanagala Oya basin
• km 12–119 · Kelani Ganga basin
• km 119–142 · Mahaweli Ganga basin

Satellite rain over these basins

• Kelani Ganga basin · Last 3 days: Rare here (1–2 days a month)
• Attanagala Oya basin · Last 3 days: Unusual here (3 days a month)
• Mahaweli Ganga basin · Last 3 days: Unusual here (3 days a month)

A whole-basin satellite average against that basin’s own record since 2000, not the area upstream of any one point. Satellites under-read hill rain. Not a warning.

Where this road crosses a river or stream

• km 8 · Dondugam Oya (Attanagala Oya basin) · flows south-west
  751 km² drain to this point · rain over that area, Last 3 days: Unusual here (3 days a month)
• km 12–13 · Old Negombo channel (Kelani Ganga basin) · 3 crossings
  0.7 km² drain to this point
• km 12 · Ja Ela (Attanagala Oya basin)
  4.8 km² drain to this point
• km 17 · Old Negombo channel (Kelani Ganga basin)
  3.4 km² drain to this point
• km 22 · Old Negombo channel (Kelani Ganga basin) · flows south-west
  50 km² drain to this point
• km 25 · Old Negombo channel (Kelani Ganga basin)
  4.3 km² drain to this point
• km 36–38 · Kelani Ganga · 2 crossings · flows south-west
  2,060 km² drain to this point · rain over that area, Last 3 days: Rare here (1–2 days a month)
  Hanwella, an Irrigation Department gauge 15 km upstream (1,820 km² upstream · rain over that area, Last 3 days: Rare here (1–2 days a month)): 3 mm in the 24 hours to 10 Nov, 08:30 (Light); 0 mm in the 3 hours to 10 Nov, 12:03.
  River level 5.6 m · Below Alert · falling over about 3 hours (Department’s thresholds: Alert 6.5, minor flood 7.5, major flood 9.5 m)
• km 38 · Maha Ela (Kelani Ganga basin) · 2 crossings
  24 km² drain to this point
• km 43–47 · Kelani Ganga · 3 crossings · flows west
  1,937 km² drain to this point · rain over that area, Last 3 days: Rare here (1–2 days a month)
  Hanwella, an Irrigation Department gauge 3.9 km upstream (1,820 km² upstream · rain over that area, Last 3 days: Rare here (1–2 days a month)): 3 mm in the 24 hours to 10 Nov, 08:30 (Light); 0 mm in the 3 hours to 10 Nov, 12:03.
  River level 5.6 m · Below Alert · falling over about 3 hours (Department’s thresholds: Alert 6.5, minor flood 7.5, major flood 9.5 m)
• km 48 · Puswell Oya (Kelani Ganga basin)
  1,937 km² drain to this point · rain over that area, Last 3 days: Rare here (1–2 days a month)
• km 69 · Gatahatta oya (Kelani Ganga basin) · flows north
  51 km² drain to this point
• km 80 · Godellakumbura Ela (Kelani Ganga basin) · flows west
  17 km² drain to this point
• km 85–88 · Kelani Ganga · 2 crossings · flows south-west
  542 km² drain to this point · rain over that area, Last 3 days: Rare here (1–2 days a month)
  Kithulgala, an Irrigation Department gauge 14.7 km upstream (425 km² upstream · rain over that area, Last 3 days: Rare here (1–2 days a month)): at least 52 mm in the 24 hours to 10 Nov, 08:30 (1 hourly reading missing); 0 mm in the 3 hours to 10 Nov, 12:02.
  River level 2.2 m · Below Alert · rising over about 3 hours (Department’s thresholds: Alert 3, minor flood 4, major flood 6 m)
• km 88 · Madelle Oya (Kelani Ganga basin) · flows north
  542 km² drain to this point · rain over that area, Last 3 days: Rare here (1–2 days a month)
• km 90 · Ekki Oya (Kelani Ganga basin) · flows west
  537 km² drain to this point · rain over that area, Last 3 days: Rare here (1–2 days a month)
• km 95 · Kelani Ganga · flows west
  506 km² drain to this point · rain over that area, Last 3 days: Rare here (1–2 days a month)
  Kithulgala, an Irrigation Department gauge 8.9 km upstream (425 km² upstream · rain over that area, Last 3 days: Rare here (1–2 days a month)): at least 52 mm in the 24 hours to 10 Nov, 08:30 (1 hourly reading missing); 0 mm in the 3 hours to 10 Nov, 12:02.
  River level 2.2 m · Below Alert · rising over about 3 hours (Department’s thresholds: Alert 3, minor flood 4, major flood 6 m)
• km 102 · Bibili Oya (Kelani Ganga basin) · flows south
  488 km² drain to this point · rain over that area, Last 3 days: Rare here (1–2 days a month)
• km 104 · Girankitte Oya (Kelani Ganga basin) · flows south-west
  470 km² drain to this point · rain over that area, Last 3 days: Rare here (1–2 days a month)
• km 107 · Kelani Ganga · flows west
  418 km² drain to this point · rain over that area, Last 3 days: Rare here (1–2 days a month)
  Kithulgala, an Irrigation Department gauge 2 km downstream (425 km² upstream · rain over that area, Last 3 days: Rare here (1–2 days a month)): at least 52 mm in the 24 hours to 10 Nov, 08:30 (1 hourly reading missing); 0 mm in the 3 hours to 10 Nov, 12:02.
  River level 2.2 m · Below Alert · rising over about 3 hours (Department’s thresholds: Alert 3, minor flood 4, major flood 6 m)
• km 120–131 · Mahaweli Ganga · 11 crossings · flows north-west
  25 km² drain to this point
• km 136 · Mahaweli Ganga · 2 crossings · flows north-west
  11 km² drain to this point

And 8 more unnamed streams on our map

Where this road runs beside a river

• km 43–44 · beside the Kelani Ganga
• km 120–121 · beside the Mahaweli Ganga
• km 122–124 · beside the Mahaweli Ganga
• km 127–129 · beside the Mahaweli Ganga
• km 136–137 · beside the Mahaweli Ganga

Rivers and basins come from our own map of Sri Lanka’s river network. Flow direction, where shown, is worked out from the height of the land. This is orientation only, not a flood warning.

The area draining to a crossing is worked out from a terrain model (about 90 m cells) and is approximate. The rain over it is the satellite average for that same area, against its own record since 2000. Areas under about 150 km² are smaller than the satellite can see, so they show no rain.

River levels are the Irrigation Department’s own readings at its gauge, against its own thresholds. This is not a flood warning: flood warnings come from the Irrigation Department and DMC.

NBRI’s advice, as issued ›

Heavy rain, up to 125 mm in 24 h

Rain gauges near your route

• 1 Katunayake, 0.8 mm, dry
• 2 Dunamale, 37.4 mm, moderate rain
• 4 Glencourse, 12 mm, moderate rain
• 9 Pambegama Tea Factory, 100.5 mm, heavy rain
• 12 Kithulgala, ≥ 52 mm, fairly heavy rain or more (incomplete day)
• 15 Laxapana, 92.8 mm, fairly heavy rain
• 17 Norton, 90 mm, fairly heavy rain
• 19 Castlereigh, 125 mm, heavy rain

12 gauges not reporting.

Gauge coverage: most of the route.

NBRI's warning stays in force after rain eases.

Satellite estimate

• Last 3 days: among the wettest 5% of 3-day periods since 2000 in Ruwanwella, Bulathkohupitiya, Yatiyanthota, Ambagamuwa +1.

Amber · Thunderstorms Amber Warning (Be Prepared)

• Amber · Thunderstorms Amber Warning (Be Prepared). Districts: Ampara, Badulla, Batticaloa, Colombo, Galle, Gampaha, Hambantota, Jaffna, Kalutara, Kandy, Kegalle, Kilinochchi, Mannar, Matale, Matara, Moneragala, Mullaitivu, Nuwara Eliya, Polonnaruwa, Ratnapura, Trincomalee, Vavuniya. Warning Description: There is an increased likelihood of severe lightning associated with thundershowers at several places in the following areas during the evening or night. Heavy falls above 100mm are likely at some places in Western, Sabaragamuwa, Central and Uva provinces and in Galle and Matara districts. Strong gusty winds of 60–70 kmph and very rough sea conditions can be expected temporarily during thundershowers in the sea areas. Action Required: • Stop paddy and plantation work, outdoor sports and construction when storms approach. • Move into a substantial building or an enclosed hard-topped vehicle; do not shelter under trees, open huts, tents or bus halts. • Avoid open fields, hilltops, beaches, tanks, rivers and other water bodies. • Fishermen and small-boat operators should not go to sea and should return to shore early. • Avoid bathing, using wired phones and handling electrical appliances during thunder. • Avoid travelling on tree-lined roads and through flooded roads. • Follow flood warnings and landslide warnings. • Protect livestock, crops and property, and be ready to move to a safe shelter if advised. Damage Expected: • Widespread thunderstorms with frequent lightning, strong gusty winds and heavy rain. • Risk of injury or death for people in open areas such as paddy fields, plantations, playgrounds, beaches, and for people on boats. • Trees uprooted and damage to roofs of non-engineered houses, including tin and thatched roofs. • Localized flash floods and slope failures in vulnerable areas. • Power and communication interruptions and damage to electrical equipment. • Damage to crops, plantations and livestock. • Dangerous conditions for small fishing boats and craft. • Disruption to road, rail and air transport. Issued 10 Nov, 12:45 · Valid until 11 Nov, 01:00.
• Forecast issued 10 Nov, 05:30
• Showers or thundershowers will occur at times in the Northern province and in Trincomalee district.
• Showers or thundershowers will occur elsewhere in the island after 1.00 p.m.
• Covers Kegalle, Nuwara Eliya and Gampaha on this road: Heavy falls above 100mm are likely at some places in Western, Sabaragamuwa, Central and Uva provinces and in Galle and Matara districts.
• Showers may occur in the coastal areas of the Southern Province during the morning.
• The general public is kindly requested to take adequate precautions to minimize damage caused by temporary localized strong winds and lightning during thundershowers.
• Covers Kegalle, Nuwara Eliya and Gampaha on this road: Misty conditions can be expected at some places in Western, Sabaragamuwa, Central and Uva provinces and in Galle, Matara and Kurunegala districts during the early hours of the morning.
• A forecast never lowers or replaces the NBRI landslide warning above.
• Forecast and advisories by the Department of Meteorology, Sri Lanka, as issued. LankaWatch is not an official service.

Crosses 13 named rivers · 3 basins · Kelani Ganga basin rain: Rare here (1–2 days a month) · rain upstream of Kelani Ganga: Rare here (1–2 days a month) · Minor flood level

Attanagala Oya · Kelani Ganga · Mahaweli Ganga

River basins along this road

• km 0–47 · Attanagala Oya basin
• km 47–134 · Kelani Ganga basin
• km 134–136 · Mahaweli Ganga basin

Satellite rain over these basins

• Kelani Ganga basin · Last 3 days: Rare here (1–2 days a month)
• Attanagala Oya basin · Last 3 days: Unusual here (3 days a month)
• Mahaweli Ganga basin · Last 3 days: Unusual here (3 days a month)

A whole-basin satellite average against that basin’s own record since 2000, not the area upstream of any one point. Satellites under-read hill rain. Not a warning.

Where this road crosses a river or stream

• km 3 · Krmbulapitiya Oya (Attanagala Oya basin)
  101 km² drain to this point
• km 23 · Diyaelle Oya (Attanagala Oya basin) · flows west
  103 km² drain to this point
• km 34 · Dondugam Oya (Attanagala Oya basin) · flows south-west
  112 km² drain to this point
  Dunamale, an Irrigation Department gauge 10.3 km downstream (150 km² upstream): 37.4 mm in the 24 hours to 10 Nov, 08:30 (Moderate); 0 mm in the 3 hours to 10 Nov, 12:03.
  River level 4.6 m · Minor flood level · steady over about 3 hours (Department’s thresholds: Alert 3.3, minor flood 4.4, major flood 5.5 m)
• km 42–43 · Woharaka Oya (Attanagala Oya basin) · 2 crossings · flows north-east
  9.2 km² drain to this point
• km 43 · Indurana Ela (Attanagala Oya basin) · flows north-west
  9.2 km² drain to this point
• km 54 · Kelani Ganga · flows south-west
  1,040 km² drain to this point · rain over that area, Last 3 days: Rare here (1–2 days a month)
  Glencourse, an Irrigation Department gauge 10.4 km downstream (1,531 km² upstream · rain over that area, Last 3 days: Rare here (1–2 days a month)): 12 mm in the 24 hours to 10 Nov, 08:30 (Moderate); 0 mm in the 3 hours to 10 Nov, 12:06.
  River level 12.55 m · Below Alert · falling over about 3 hours (Department’s thresholds: Alert 15, minor flood 15.5, major flood 19 m)
• km 55 · Gurugoda Oya (Kelani Ganga basin) · flows south
  1,032 km² drain to this point · rain over that area, Last 3 days: Rare here (1–2 days a month)
  Holombuwa, an Irrigation Department gauge 18.3 km upstream (154 km² upstream · rain over that area, Last 3 days: Rare here (1–2 days a month)): at least 3.9 mm in the 24 hours to 10 Nov, 08:30 (1 hourly reading missing); 0 mm in the 3 hours to 10 Nov, 12:05.
  River level 1.2 m · Below Alert · falling over about 3 hours (Department’s thresholds: Alert 3, minor flood 4, major flood 6 m)
• km 59–64 · Ritigaha Oya (Kelani Ganga basin) · 7 crossings · flows south
  82 km² drain to this point
• km 69 · We Oya (Kelani Ganga basin) · flows south-west
  73 km² drain to this point
• km 73 · Ekki Oya (Kelani Ganga basin) · flows west
  537 km² drain to this point · rain over that area, Last 3 days: Rare here (1–2 days a month)
• km 78 · Kelani Ganga · flows west
  506 km² drain to this point · rain over that area, Last 3 days: Rare here (1–2 days a month)
  Kithulgala, an Irrigation Department gauge 8.9 km upstream (425 km² upstream · rain over that area, Last 3 days: Rare here (1–2 days a month)): at least 52 mm in the 24 hours to 10 Nov, 08:30 (1 hourly reading missing); 0 mm in the 3 hours to 10 Nov, 12:02.
  River level 2.2 m · Below Alert · rising over about 3 hours (Department’s thresholds: Alert 3, minor flood 4, major flood 6 m)
• km 84 · Bibili Oya (Kelani Ganga basin) · flows south
  488 km² drain to this point · rain over that area, Last 3 days: Rare here (1–2 days a month)
• km 87 · Girankitte Oya (Kelani Ganga basin) · flows south-west
  470 km² drain to this point · rain over that area, Last 3 days: Rare here (1–2 days a month)
• km 90 · Kelani Ganga · flows west
  418 km² drain to this point · rain over that area, Last 3 days: Rare here (1–2 days a month)
  Kithulgala, an Irrigation Department gauge 2 km downstream (425 km² upstream · rain over that area, Last 3 days: Rare here (1–2 days a month)): at least 52 mm in the 24 hours to 10 Nov, 08:30 (1 hourly reading missing); 0 mm in the 3 hours to 10 Nov, 12:02.
  River level 2.2 m · Below Alert · rising over about 3 hours (Department’s thresholds: Alert 3, minor flood 4, major flood 6 m)
• km 119–125 · Kehelgama Ganga (Kelani Ganga basin) · 7 crossings · flows north-west
  148 km² drain to this point

And 3 more unnamed streams on our map

Where this road runs beside a river

• km 60–61 · beside the Ritigaha Oya
• km 62–64 · beside the Ritigaha Oya
• km 122–123 · beside the Kehelgama Ganga
• km 123–125 · beside the Kehelgama Ganga

Rivers and basins come from our own map of Sri Lanka’s river network. Flow direction, where shown, is worked out from the height of the land. This is orientation only, not a flood warning.

The area draining to a crossing is worked out from a terrain model (about 90 m cells) and is approximate. The rain over it is the satellite average for that same area, against its own record since 2000. Areas under about 150 km² are smaller than the satellite can see, so they show no rain.

River levels are the Irrigation Department’s own readings at its gauge, against its own thresholds. This is not a flood warning: flood warnings come from the Irrigation Department and DMC.

NBRI’s advice, as issued ›

Fairly heavy rain, up to 90 mm in 24 h

Rain gauges near your route

• 1 Katunayake, 0.8 mm, dry
• 2 Badalgama, 6 mm, light rain
• 16 Nawalapitiya, 77.2 mm, fairly heavy rain
• 20 Norton, 90 mm, fairly heavy rain

18 gauges not reporting.

Gauge coverage: most of the route.

NBRI's warning stays in force after rain eases.

Satellite estimate

• Last 3 days: among the wettest 5% of 3-day periods since 2000 in Warakapola, Galigamuwa, Kegalle, Rambukkana +8.

Amber · Thunderstorms Amber Warning (Be Prepared)

• Amber · Thunderstorms Amber Warning (Be Prepared). Districts: Ampara, Badulla, Batticaloa, Colombo, Galle, Gampaha, Hambantota, Jaffna, Kalutara, Kandy, Kegalle, Kilinochchi, Mannar, Matale, Matara, Moneragala, Mullaitivu, Nuwara Eliya, Polonnaruwa, Ratnapura, Trincomalee, Vavuniya. Warning Description: There is an increased likelihood of severe lightning associated with thundershowers at several places in the following areas during the evening or night. Heavy falls above 100mm are likely at some places in Western, Sabaragamuwa, Central and Uva provinces and in Galle and Matara districts. Strong gusty winds of 60–70 kmph and very rough sea conditions can be expected temporarily during thundershowers in the sea areas. Action Required: • Stop paddy and plantation work, outdoor sports and construction when storms approach. • Move into a substantial building or an enclosed hard-topped vehicle; do not shelter under trees, open huts, tents or bus halts. • Avoid open fields, hilltops, beaches, tanks, rivers and other water bodies. • Fishermen and small-boat operators should not go to sea and should return to shore early. • Avoid bathing, using wired phones and handling electrical appliances during thunder. • Avoid travelling on tree-lined roads and through flooded roads. • Follow flood warnings and landslide warnings. • Protect livestock, crops and property, and be ready to move to a safe shelter if advised. Damage Expected: • Widespread thunderstorms with frequent lightning, strong gusty winds and heavy rain. • Risk of injury or death for people in open areas such as paddy fields, plantations, playgrounds, beaches, and for people on boats. • Trees uprooted and damage to roofs of non-engineered houses, including tin and thatched roofs. • Localized flash floods and slope failures in vulnerable areas. • Power and communication interruptions and damage to electrical equipment. • Damage to crops, plantations and livestock. • Dangerous conditions for small fishing boats and craft. • Disruption to road, rail and air transport. Issued 10 Nov, 12:45 · Valid until 11 Nov, 01:00.
• Forecast issued 10 Nov, 05:30
• Showers or thundershowers will occur at times in the Northern province and in Trincomalee district.
• Showers or thundershowers will occur elsewhere in the island after 1.00 p.m.
• Covers Kegalle, Kandy, Nuwara Eliya and Gampaha on this road: Heavy falls above 100mm are likely at some places in Western, Sabaragamuwa, Central and Uva provinces and in Galle and Matara districts.
• Showers may occur in the coastal areas of the Southern Province during the morning.
• The general public is kindly requested to take adequate precautions to minimize damage caused by temporary localized strong winds and lightning during thundershowers.
• Covers Kegalle, Kandy, Nuwara Eliya and Gampaha on this road: Misty conditions can be expected at some places in Western, Sabaragamuwa, Central and Uva provinces and in Galle, Matara and Kurunegala districts during the early hours of the morning.
• A forecast never lowers or replaces the NBRI landslide warning above.
• Forecast and advisories by the Department of Meteorology, Sri Lanka, as issued. LankaWatch is not an official service.

Crosses 8 named rivers · 3 basins · rain upstream of Maha Oya: Rare here (1–2 days a month)

Attanagala Oya · Maha Oya · Mahaweli Ganga

River basins along this road

• km 0–5 · Attanagala Oya basin
• km 5–32 · Maha Oya basin
• km 32–37 · Attanagala Oya basin
• km 37–89 · Maha Oya basin
• km 89–93 · Mahaweli Ganga basin
• km 93–99 · Maha Oya basin
• km 99–157 · Mahaweli Ganga basin

Satellite rain over these basins

• Attanagala Oya basin · Last 3 days: Unusual here (3 days a month)
• Maha Oya basin · Last 3 days: Unusual here (3 days a month)
• Mahaweli Ganga basin · Last 3 days: Unusual here (3 days a month)

A whole-basin satellite average against that basin’s own record since 2000, not the area upstream of any one point. Satellites under-read hill rain. Not a warning.

Where this road crosses a river or stream

• km 3 · Krmbulapitiya Oya (Attanagala Oya basin)
  101 km² drain to this point
• km 16 · Dunagaha Ela (Attanagala Oya basin) · flows west
  24 km² drain to this point
• km 25 · Kuda Oya (Maha Oya basin) · flows north
  8.1 km² drain to this point
• km 46–48 · Kuda Oya (Maha Oya basin) · 2 crossings · flows north
  54 km² drain to this point
• km 55 · Rogala Oya (Maha Oya basin) · flows north-east
  3.6 km² drain to this point
• km 56–58 · Galigamuwa Oya (Maha Oya basin) · 2 crossings · flows west
  8.5 km² drain to this point
• km 79 · Maha Oya · flows west
  199 km² drain to this point · rain over that area, Last 3 days: Rare here (1–2 days a month)
• km 81–83 · Hingul Oya (Maha Oya basin) · 3 crossings · flows west
  39 km² drain to this point
• km 117–122 · Mahaweli Ganga · 4 crossings · flows north
  187 km² drain to this point · rain over that area, Last 3 days: Rare here (1–2 days a month)
  Nawalapitiya, an Irrigation Department gauge 1.2 km upstream (187 km² upstream · rain over that area, Last 3 days: Rare here (1–2 days a month)): 77.2 mm in the 24 hours to 10 Nov, 08:30 (Fairly heavy); 0 mm in the 3 hours to 10 Nov, 12:01.
  River level 1.62 m · Below Alert · falling over about 3 hours (Department’s thresholds: Alert 3.5, minor flood 5, major flood 6 m)
• km 127–146 · Mahaweli Ganga · 17 crossings · flows north-west
  25 km² drain to this point
• km 151 · Mahaweli Ganga · 2 crossings · flows north-west
  11 km² drain to this point

And 4 more unnamed streams on our map

Where this road runs beside a river

• km 82–83 · beside the Hingul Oya
• km 116–117 · beside the Mahaweli Ganga
• km 133–134 · beside the Mahaweli Ganga
• km 135–136 · beside the Mahaweli Ganga
• km 137–139 · beside the Mahaweli Ganga
• km 142–144 · beside the Mahaweli Ganga
• km 151–152 · beside the Mahaweli Ganga

Rivers and basins come from our own map of Sri Lanka’s river network. Flow direction, where shown, is worked out from the height of the land. This is orientation only, not a flood warning.

The area draining to a crossing is worked out from a terrain model (about 90 m cells) and is approximate. The rain over it is the satellite average for that same area, against its own record since 2000. Areas under about 150 km² are smaller than the satellite can see, so they show no rain.

River levels are the Irrigation Department’s own readings at its gauge, against its own thresholds. This is not a flood warning: flood warnings come from the Irrigation Department and DMC.

Watch · NBRI adviceSince the rainfall within the past 24 hours has exceeded 75mm, if the rain continues, be watchful on the possibility of landslides, slope failures, rock falls, cutting failures and ground subsidence.

NBRI, issued Mon 9 Nov, 20:00 · valid to Tue 10 Nov, 20:00