The row that erupted in the Kerala Legislative Assembly on Wednesday over Tamil Nadu’s ownership of four dams located in the territory of Kerala has come as a surprise to water experts here.

The dams in question — Mullaperiyar, Parambikulam, Tunacadavu and Peruvaripallam — have long been under the control of Tamil Nadu, they point out.

While the Mullaperiyar, the most prominent among them, is covered under the 1886 agreement, the other three dams fall under the purview of the 1958 inter-State agreement.

Pointing out that these facts are well known and have been in the public domain for years, an expert says it is a settled matter that all these dams “are owned, operated and maintained by Tamil Nadu”. This position has been specifically reflected in the two inter-State pacts.

When the controversy broke out eight years ago after the Kerala Assembly adopted the Kerala Irrigation and Water Conservation (Amendment) Act, 2006, that prescribed the full-water level for a number of dams including the Mullaperiyar, the question of Tamil Nadu’s ownership over the dam in dispute was discussed, both in and outside the Supreme Court.

The judgement of the Apex Court has also recorded that the dam is “owned and operated by the Government of Tamil Nadu”.

Two years ago, when the Central government had circulated the draft Dam Safety Bill, Chief Minister Jayalalithaa had expressed reservations over the legislation on various grounds.

She had stated that certain provisions of the Bill would directly interfere with the safety and the functioning of the dams owned, operated and maintained by a State government, in a situation wherein they were located in another State.