Waves of rain

1. At a Glance

• The 2026 monsoon in Odisha is one of its most intense. It is driven by repeated weather systems over the Bay of Bengal, not by strong all-India monsoon behaviour [1].
• The core idea is compounding (back-to-back) rainfall. A previous spell saturates the soil and fills local storage, so each new spell turns into immediate runoff and floods [1].
• The event is a UPSC case study linking monsoon variability, El Niño, forecast limits, geomorphology (deltaic coast vs highland south), urban drainage and disaster governance (Odisha's zero-casualty policy, CAG audit findings) [1].
• It shows why state-level rainfall can diverge sharply from the all-India seasonal forecast [1].

2. Why in the News

• Between June and 25 Sept 2026, Odisha recorded 1,453 mm of rain, a 29% excess [1].
• 11 atmospheric systems formed over the Bay of Bengal this season. The latest made landfall near Kalingapatnam on 23 Sept 2026 [1].
• The rain caused floods in Bhadrak and Jajpur and landslides in hilly areas [1].
• The Hindu editorial of 29 Sept 2026 (Chennai edition, p. 8) said Odisha "must prepare for repeated bouts of intense downpour" [1].

3. Background & Evolution

• Pre-season forecast: IMD expected India to get 90% of the Long Period Average (LPA). This was partly because an El Niño was expected to develop [1].
• June 2026: Odisha ended June with a 47% deficit [1].
• July–Sept 2026: Rain came to be dominated by weather systems over the Bay of Bengal. These delivered rain repeatedly without giving people time to recover [1].
• By 30 July 2026: State estimates put the number of people affected at 5.2 lakh [1].
• By 27 Aug 2026: Another 13.5 lakh people were affected [1].
• 23 Sept 2026: The latest system made landfall near Kalingapatnam [1].
• Up to 25 Sept 2026: Cumulative rain reached 1,453 mm, a 29% excess [1].
• Earlier precedent ‡: The 1999 Odisha Super Cyclone led to the creation of the Odisha State Disaster Management Authority (OSDMA). It is the origin of Odisha's focus on cutting casualties. (‡ not from a retrieved source)

4. Core Static Facts

Item	Fact
Odisha seasonal rain (June–25 Sept 2026)	1,453 mm, +29% [1]
June 2026 departure	−47% [1]
Bay of Bengal systems in 2026 season	11 [1]
Latest landfall	Near Kalingapatnam, 23 Sept 2026 [1]
IMD all-India forecast	90% of LPA [1]
Stated reason for low forecast	Expected El Niño [1]
Locations with more than 100 mm in 24 h	At least 60 [1]
People affected	5.2 lakh (by 30 July) + 13.5 lakh (by 27 Aug) [1]
Flood-hit districts named	Bhadrak, Jajpur [1]
Terrain of the south	Mostly highland, so slope-failure (landslide) risk [1]
Terrain of the coast	Depositional plain of multiple deltas, low gradient, poor drainage to the sea [1]
State policy	Zero casualties [1]
Audit body that flagged drain deficiencies	CAG [1]

Standard reference points ‡ (not from a retrieved source; check before use):

• IMD comes under the Ministry of Earth Sciences.
• The all-India LPA for June–September is about 87 cm, based on the 1971–2020 average.
• IMD seasonal categories:
• Deficient: below 90% of LPA
• Below normal: 90–95%
• Normal: 96–104%
• Above normal: 105–110%

• Excess: above 110%

• IMD daily rainfall categories:

• Heavy: 64.5–115.5 mm
• Very heavy: 115.6–204.4 mm

• Extremely heavy: 204.5 mm or more

• Kalingapatnam is on the north coast of Andhra Pradesh (Srikakulam district), near the Odisha border.

5. Multi-Dimensional Analysis

Environmental / Geographical

• Coastal Odisha is a low-gradient depositional plain of multiple deltas, so floodwater drains slowly to the sea [1].
• The southern highlands face slope failure and landslides under saturated conditions [1].
• Runoff from repeated spells swells several rivers at once and pushes the flood risk downstream (Bhadrak, Jajpur) [1].

Scientific / Technological (forecasting)

• The all-India seasonal outlook (90% of LPA, based on El Niño) did not capture regional rain driven by weather systems [1].
• Antecedent soil moisture matters. The same amount of rain causes more runoff when the soil is already saturated. This argues for impact-based, cumulative-rain forecasting [1].
• A June deficit of 47% turned into a seasonal excess of 29%. This shows how much rainfall can swing within one season [1].

Social

• About 18.7 lakh people were affected in two waves (5.2 lakh + 13.5 lakh) [1].
• Repeated spells deny recovery time, which deepens the losses for vulnerable households [1].

Governance / Administrative

• Odisha's zero-casualty policy now faces a multi-wave test, not a single cyclone [1].
• The CAG had flagged deficiencies in drain design and maintenance. This season will put those weaknesses under strain [1].
• The lesson is that disaster preparedness should shift from single-event response to season-long resilience planning [1].

Economic

• Repeated flooding in delta districts threatens farming, infrastructure and livelihoods. The article gives no specific loss figures [1].

6. Recent Developments (last 12–18 months)

• June 2026: Odisha ended the month with a 47% rainfall deficit [1].
• 30 July 2026: 5.2 lakh people affected, as estimated by the state [1].
• 27 Aug 2026: Another 13.5 lakh people affected [1].
• 23 Sept 2026: The 11th Bay of Bengal system of the season made landfall near Kalingapatnam [1].
• 25 Sept 2026: Seasonal total reached 1,453 mm, 29% above normal [1].
• 29 Sept 2026: The Hindu editorial "Waves of rain" called for preparation against repeated downpours [1].

7. Prelims Hooks

• Odisha received 1,453 mm of rain between June and 25 Sept 2026, a 29% excess [1].
• 11 atmospheric systems formed over the Bay of Bengal in the 2026 monsoon season [1].
• The latest 2026 system made landfall near Kalingapatnam on 23 Sept 2026 [1].
• IMD had forecast India's 2026 monsoon at 90% of LPA, partly because of an expected El Niño [1].
• Odisha ended June 2026 with a 47% rainfall deficit [1].
• At least 60 locations in Odisha got more than 100 mm in 24 hours [1].
• Flood risk was highlighted downstream in Bhadrak and Jajpur districts [1].
• Coastal Odisha is a depositional plain of multiple deltas with a low gradient [1].
• Southern Odisha is mostly highland, prone to slope failure [1].
• Odisha has a long-standing zero-casualty disaster policy [1].
• The CAG flagged drain design and maintenance deficiencies in Odisha [1].
• ‡ IMD comes under the Ministry of Earth Sciences, not MoEFCC (not from a retrieved source).
• ‡ "Normal" seasonal rainfall means 96–104% of LPA (not from a retrieved source).

8. Why Zero Deaths Is Not the Same as Zero Damage

• Odisha's success is counted in lives saved, but this flood's losses are in lives disrupted
• The zero-casualty goal checks one thing: did anyone die? [1]
• By 18 Aug 2026, floods had damaged nearly 42,000 hectares of farmland in six districts: Balasore, Bhadrak, Jajpur, Mayurbhanj, Kendrapara and Keonjhar [2].

• A family can survive every wave and still lose its crop, its savings and its wages. The zero-casualty score does not show any of that.

• Crop compensation is paid per hectare, so people with no land get the least

• The state announced a Rs 1,000 crore relief package. It pays Rs 8,500 per hectare for non-irrigated land, Rs 17,000 for irrigated land and Rs 22,500 for perennial crops (crops that stay in the field for years, like fruit trees) [2].

• A landless agricultural labourer owns no hectare. What they lose is daily work, and the per-hectare formula does not pay for that [2].

• The claim process assumes people can travel and have their papers

• A person with a disability may not be able to reach a government office to file a claim [2].
• A single woman who has lost her income while caring for children faces the same problem, and so does an elderly person living alone [2].

• So the people least able to recover are also the least likely to be paid.

• The fair counter-argument, and its limit

• The state did act quickly: it evacuated 3.3 lakh people to relief camps by 18 Aug and announced a package for the worst-hit districts [2].
• That is real capacity, and many states lack it.
• But relief built around evacuation and crop loss leaves out the landless, the disabled and the elderly. Those groups are exactly the ones the zero-casualty measure cannot see [2].

9. What Worked Against Cyclones and Why It Only Partly Works for Floods

• The cyclone model was built for one big blow
• Before Cyclone Phailin in 2013, Odisha evacuated close to 1 million people. Fewer than 50 people died [3].

• A cyclone has one landfall, a warning a few days ahead, and one evacuation. After it passes, people go home.

• Monsoon waves break that pattern

• This season brought 11 weather systems from the Bay of Bengal, one after another [1].
• Each spell falls on soil that is already wet, so the danger keeps building over weeks. It does not come and go in a single day [1].

• Evacuation saves lives each time. But when people are moved again and again, they cannot sow, earn or repair their homes between waves [1][2].

• The hazard is also in a different place

• The cyclone system was built for the coast [3].
• This season also brought landslides (slope failure) in the southern highlands, and floods in inland districts like Mayurbhanj and Keonjhar [1][2].
• Rain gauges, warnings and shelters built for the coast do not automatically cover these areas.

10. Why Flood Works Keep Failing the Same Way

• India builds flood works, then leaves them without money for upkeep
• A CAG audit (Comptroller and Auditor General, India's top government auditor) of the Flood Management Programme (FMP), the Centre's scheme that funds states' flood-control works, found that Assam and Jammu & Kashmir had no separate maintenance programme and no dedicated funding once a project was finished [4].

• The CAG also flagged Odisha's drains for weak design and poor maintenance [1]. It is the same pattern: build once, never maintain.

• Works built without studying the river fail when the river rises

• In Assam and West Bengal, Rs 16.72 crore was spent on flood protection, yet the areas still flooded. No one had blocked backflow (river water pushing back up through the drains) [4].
• In some states, projects went ahead without a morphological study (a study of how a river's shape and course change over time) or soil surveys [4].

• On Odisha's flat delta coast, water already drains slowly to the sea [1]. A drain or sluice built without these studies is most likely to fail exactly here.

• Approvals move too slowly for a changing climate

• Approval of 39 FMP projects was delayed by up to 13 years, held up at the DPR stage (Detailed Project Report, the full technical plan) [4].
• 13 stalled projects left Rs 59.88 crore spent with nothing to show for it [4].
• These findings are national. The article does not give Odisha-specific CAG figures for the FMP, so use them to show a pattern, not as Odisha data [4].

11. How to Read the Numbers in This Story

• A seasonal percentage does not measure harm
• '+29%' is a total for the whole season [1]. It cannot tell a gentle, spread-out season apart from one that came in a few violent bursts.

• What predicts floods is how much rain falls in a short time: at least 60 places got more than 100 mm in 24 hours [1]. Soil that was already wet matters too [1].

• Affected-people figures change week to week. Always quote the date

• One count gives 9.4 lakh people affected by 18 Aug 2026 [2].
• The state figure used in the editorial is 13.5 lakh by 27 Aug [1].
• These are running counts, and different sources use different cut-off dates. In an answer, write the figure with its date and source. Do not add them together unless you know they cover separate periods.

12. Who Should Do What Before the Next Wave

• IMD (under MoES) should warn on cumulative rain, not just the next day's rain
• The same rain causes more runoff (water flowing over the ground instead of soaking in) when earlier spells have already soaked the soil [1].

• A warning that adds up the last few days' rain would show district officials when an ordinary forecast has turned dangerous.

• Odisha's Water Resources Department should keep a separate budget line for maintaining drains and embankments

• The CAG found that flood works with no funding after completion break down [4], and it flagged Odisha's drains specifically [1].

• Money set aside for maintenance each year, before the monsoon, fixes the exact fault the audit found.

• The Revenue and Disaster Management Department should take relief to people's doors

• Right now, compensation reaches people who can travel and who own land [2].

• Recovery should be 'disability-inclusive, gender-responsive and age-sensitive'. That means field teams going to the landless, the disabled and elderly people living alone [2].

• OSDMA should reuse its cyclone strength for floods

• The community network that moved about 1 million people before Phailin [3] can be given flood and landslide tasks. For example, it could watch slopes in the highland south and keep lists of households that must be moved first.

13. Anchors for Answers

• Data: Odisha got 1,453 mm (+29%) from 11 Bay of Bengal systems; at least 60 locations had more than 100 mm in 24 hours [1]
• Data: About 42,000 ha of farmland damaged and 3.3 lakh people in relief camps by 18 Aug 2026; Rs 1,000 crore relief package [2]
• Data: Cyclone Phailin (2013): close to 1 million evacuated, fewer than 50 deaths [3]
• Report/Committee: CAG audit of the Flood Management Programme (reported July 2017): approvals of 39 projects delayed by up to 13 years; Rs 59.88 crore spent on 13 stalled projects with no result; no funding for maintenance after completion [4]
• Law/Case: Disaster Management Act, 2005: the statutory basis for NDMA and the state disaster management authorities
• Scheme: Flood Management Programme: the Centre's funding for state flood-control works, with its maintenance gap flagged by the CAG [4]

14. Mains Relevance

• GS-I (Geography):
• Salient features of world physical geography
• Important geophysical phenomena (floods, landslides)
• Distribution of monsoon rainfall

• Deltaic landforms

• GS-III:

• Disaster and disaster management
• Climate change and extreme weather

• Infrastructure (urban drainage)

• GS-II (secondary): Role of the CAG, and Centre–state roles in disaster governance.

Plausible question stems:

1. An all-India 'below-normal' monsoon forecast can coexist with regional floods. Explain with reference to Odisha's 2026 monsoon, and suggest reforms in forecasting and early warning.
2. Repeated rainfall spells convert moderate rain into disasters. Discuss the role of antecedent conditions and terrain in flood and landslide risk in coastal and highland Odisha.
3. Odisha's 'zero-casualty' approach succeeded against cyclones. Evaluate whether it is adequate for multi-hazard, multi-wave monsoon events.

15. Related Topics to Study Next

• El Niño–Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD): these drive the monsoon forecast and explain why regional outcomes differ.
• Monsoon low-pressure systems and depressions over the Bay of Bengal: the mechanism behind the 11 systems.
• IMD rainfall classification and Long Period Average (LPA): needed to interpret forecasts and departures.
• Mahanadi–Brahmani–Baitarani delta system: explains the low-gradient coast and floods in Bhadrak and Jajpur.
• Odisha Super Cyclone 1999 and OSDMA: the origin of Odisha's disaster-management model.
• Disaster Management Act, 2005 and NDMA flood/landslide guidelines: the statutory framework.
• Urban flooding and stormwater drainage: connects to the drainage deficiencies CAG flagged.
• Impact-based forecasting and early-warning systems: the policy fix for compounding rainfall.

16. Common Errors / Trap Areas

• Confusing all-India with regional outcomes. A forecast of 90% of LPA for India does not mean every state gets deficient rain. Odisha got a 29% excess [1].
• Kalingapatnam's location. The landfall point is not in Odisha ‡. It lies on the north Andhra Pradesh coast (not from a retrieved source).
• Counting affected people. The 5.2 lakh (by 30 July) and 13.5 lakh (by 27 Aug) figures are separate waves. Do not report either one as the season total [1].
• Ministry trap ‡. IMD comes under MoES, not MoEFCC or MHA. NDMA comes under MHA (not from a retrieved source).
• Terrain mix-up. The coast floods because of its low-gradient deltas. The south faces landslides because it is highland. Do not swap the hazards [1].