The Obeid-linked water company at the centre of conflict of interest allegations that are before the Independent Commission Against Corruption made multiple donations to the Liberal Party as it sought political favour, including a direct donation of $10,000 to Joe Hockey's federal electorate committee in 2010 - just weeks before the election that year.

The link is the first evidence tying Australian Water Holdings (AWH) to the Treasurer and is revealed in the Australian Electoral Commission's Donor to Political Party Disclosure Return - Organisations report for the financial year 2010-11.

Corruption hearing: Obeid-linked water company gave $10,000. Credit:Peter Rae

The donation to the ''North Sydney FEC'' was by far the largest single donation to an electorate fund made by AWH, although another gift of $10,000 was made to the National Party of Australia, based in Canberra, and a donation of $30,000 was paid to the Liberal Party NSW Division in December 2010.

The donation to North Sydney FEC was paid back in February last year - $11,000, which was $10,000 plus GST - after reports began to circulate about corruption concerns at AWH.