The concept of 'surplus' and 'deficit' river basins is hydrologically contested. Discuss with reference to the Ken–Betwa Link Project.

India's National Perspective Plan (1980) proposes moving water from "surplus" to "deficit" basins through 30 links [3]. The Ken–Betwa Link Project (KBLP) is its first test case [2]. The idea is sound as a goal, but labelling a basin "surplus" depends on assumptions that hydrology does not fully support.

Why the surplus–deficit idea appeals

• Uneven spread of water: the plan seeks to move about 174 BCM of water and add about 34,000 MW of hydropower [1].
• Drought relief in Bundelkhand: KBLP aims to irrigate 10.62 lakh ha and supply drinking water to about 62 lakh people through a 216 km canal from the Daudhan Dam [2].
• Cooperative federalism: Madhya Pradesh and Uttar Pradesh signed an MoA (2021), and the Centre funds most of the project [2].

Why the labels are contested

• Averages hide variation: "surplus" comes from long-term average flows. These averages hide monsoon-only flows and year-to-year swings [1]. A river can have spare water in August and too little in May.
• The Ken is in Bundelkhand too: the donor river runs through the same drought-prone region it is meant to relieve [2]. This raises doubts about how reliable its "surplus" is in dry years.
• Nature's share is ignored: water left in a river keeps sediment moving, floodplains and deltas healthy, and fish migrating [1]. Calling that water "surplus" leaves out environmental flows.
• Costs at the donor end: the Daudhan reservoir will flood about 9,000 ha, including 4,141 ha of Panna Tiger Reserve's core area and 10 villages [4].
• Biological costs: an ATREE study warns that canals can become "highways" for invasive species, which could make distinct basins more alike (biotic homogenisation) [1]. Ken–Betwa joins two Yamuna tributaries, so its invasion risk is relatively low. Links between separate basins carry much greater risk [1].

Way forward

• Use seasonal, dynamic water accounting instead of fixed averages.
• Set aside environmental flows before declaring any surplus.
• Introduce network-level cumulative EIA and invasive-species screening [1].
• Combine transfers with demand-side steps such as micro-irrigation and tank revival [2].

Overall, "surplus" and "deficit" depend on season and on ecology. KBLP shows both the real human need behind river-linking and the hidden costs of that framing. River-linking can support water security (SDG 6) and protect life on land (SDG 15) if each link is approved on the basis of dynamic hydrology and ecological safeguards rather than fixed labels.