What happens next, and how long?

After the PFR: what steps would follow, and how long?

The steps described for SUMP – Siang Upper Multipurpose Project, with the time each one takes. The government has assured that if people do not want the project after the PFR, it stops right there.

A small drilling machine on a grassy riverbank with one worker; a big callout reads 3–6 months, with the timeline bar.

Step 1: the PFR

A short study of the land. It takes 3 to 6 months. Four machines drill to collect rock samples. There is no loss and no effect on the environment, on the people, or on anyone. It is not an approval.

Adi villagers in traditional dress seated at a village consultation under a bamboo shelter; callout 2–3 years, with the timeline bar.

Step 2: the studies

Only if the PFR finds the project workable and the site suitable. The study of effects on people, the environmental study and the environmental management plan take 2 to 3 years together. The Gram Sabha and Panchayat must take part in the study of effects on people, and public consultations are held.

Image, seen from above, of a thick bound project report open on an outdoor table by a river, its pages showing a map, a river cross-section, charts and site photos, three engineers leaning over it; callout 3–4 years, with the timeline bar.

Step 3: the DPR

If the project goes ahead. Finalising the Detailed Project Report (DPR) takes 3 to 4 years. It examines the project from every angle for safety, including earthquake safety. The government has assured that compensation and the R&R plan would be finalised then, through public consultations.

The government has assured: if people do not want the project after the PFR, it stops right there, with no further action. A hillside village above a full calm river with Adi villagers in traditional dress on the bank; callout 14–15 years, the timeline bar, and the highlighted assurance line.

Step 4: construction

If the project goes ahead after all these steps, building it would take 14 to 15 years, and power generation would be expected around 2046 to 2047.

Is it safe in an earthquake zone?

The government has made it clear that, if the project goes ahead, the Detailed Project Report (DPR) examines the project from all possible angles for safety, security and feasibility, including earthquake safety.

The area is in Seismic Zone V. The project would be designed to safeguard against earthquakes as per the seismicity of that exact site.

A 15-member national committee on earthquake design would guide the design during the DPR stage.

Site-specific studies, drilling and rock testing will check the earthquake risk before any decision is taken.

Safety of such projects in India is governed by the Dam Safety Act, 2021, which sets uniform safety standards across the country. An early warning system and an Emergency Action Plan would be set up under the National Dam Safety Authority Rules.

India has the technical ability to carry out all the required safety studies. For example, the Subansiri Lower project is designed to withstand an 8.5-magnitude earthquake.

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