UPDATE 1-Serco says on track to meet expectations

* Says trading remains strong in H1, good cash flow

* Wins 180 mln stg deal with Australian government

(Adds detail)

LONDON, June 29 (Reuters) - British support services company Serco (SRP.L) said on Monday it remained on track to meet expectations for 2009 thanks to a sustained high-level of activity in the first-half.

Serco said it had won a five-year contract with the Australian government, worth 180 million pounds, to manage and operate seven adult immigration detention centres. Serco was the preferred bidder for the project. The blue-chip company added it expects a "modest increase" in working capital investment in the first half compared to last year.

(Reporting by Lorraine Turner)