The Convention in its article 9, paragraph 1, obliges Parties, inter alia, to enter into bilateral or multilateral agreements or other arrangements, where these do not yet exist, or adapt existing ones, where necessary to eliminate the contradictions with the basic principles of the Convention.

UNECE records date back to 1858 when Austria and Bavaria signed the agreement concerning the regulation and management of the river Inn from its jonction with the Salzach at Rothenbuch to the point where it discharges into the Danube at Passau. In 1863, Belgium and the Netherlands signed the treaty concerning the regulation of water supply from the Meuse. Germany and Switzerland concluded in 1890 the agreement concerning the hydropower station at Rheinfelden. The first and still existing agreement covering both water-quality and water-quantity issues, and even setting up a joint body, is the 1909 treaty between Great Britain and the United States of America relating to boundary waters and questions arising along the boundary between Canada and the United States, and the establishment of an international joint commission.

In 1993, the secretariat published a list of Bilateral and Multilateral Agreements and other Arragements in Europe and North America on the Protection and Use of Transboundary Waters. The list was further updated in 1995 and 1996.

In 1999, as a result of the discussion of the Working Group on Water Management, a questionnaire was sent to UNECE Member States in order to gather information on their policies and strategies for the protection and use of transboundary waters. Parties and non-Parties reported that a number of existing agreements have been revised in the 1990s. Moreover, new bilateral and multilateral agreements have been drawn up, signed and ratified, respectively, or entered into force. Thus, currently more than 150 agreements on transboundary waters exist in the region.

It followed from the replies to the 1999 questionnaire that - with the exception of five catchment areas - all Parties to the Convention bordering the same transboundary waters have drawn up, signed and/or ratified agreements on the protection and use of transboundary waters. For the remaining catchment areas, the conclusion of agreements is expected by 2003.

In 2003, UNECE, together with UNEP, the Swedish Environmental Protection Agency, the Russian Ministry of Natural Resources and the NGO Ecoterra (Moscow), organized a workshop in Moscow (31 March - 1 April 2003) to analyse experience gained in East European, Caucasian and Central Asian (EECCA) countries in concluding and implementing international legal instruments on the protection and use of waters and examine difficulties encountered when implementing the Convention. The workshop report "Transboundary Water Cooperation in the newly independent States (NIS)" includes a list of recent agreements signed in the NIS (English version, 570KB; Russian version, 840KB)