Punjab's dispute with Haryana and Rajasthan over the waters of the Ravi and Beas has run since before Haryana existed.
Punjab's position rests on riparian principle: the rivers run through Punjab and not through Haryana or Rajasthan, and under the doctrine applied to interstate rivers elsewhere in India a non-riparian state has no claim. The counter-position rests on the 1955 allocation, on the 1976 central award and on the 1981 agreement signed by the Punjab government of the day.
The Satluj Yamuna Link canal was to carry Haryana's share. Construction began in 1982. It has never been completed. In 1990 the chief engineer and the superintending engineer of the project were shot dead. In 2004 the Punjab Assembly passed an Act terminating all its water agreements. The Supreme Court held that Act unconstitutional in 2016.
Meanwhile Punjab's groundwater has been drawn down by paddy cultivation to the point where a majority of its blocks are classed as over-exploited, and the state's own agriculture department projects severe scarcity within decades.
The dispute is usually reported as a political quarrel between two states. It is also a question about whether the water exists at all.
The dispute is over the Ravi and the Beas surplus and it runs between Punjab, Haryana and Rajasthan, with the Sutlej Yamuna Link canal as its physical form.
Punjab's position is that it has no surplus to give and that riparian principle should govern. Haryana's is that the 1966 reorganisation entitles it to a share of what Punjab holds.
The canal was partly built, the work stopped in 1990, and the litigation has run through the Supreme Court repeatedly since. Nothing about it has been resolved in thirty-five years.