** Shares of Downer EDI DOW.AX rise as much as 2.7% to A$7.740, hitting its highest level since March 6
** Stock logs best trading day since March 10
** Infrastructure co says it had been awarded A$500 million ($350.85 million) long-term partnering agreement with Stockland SGP.AX
** Adds, under deal co to deliver services across SGP's operational assets across New South Wales, Western Australia, Victoria and Queensland
** Stock down 3.5% this year, including the day's move
($1 = 1.4251 Australian dollars)
(Reporting by Rajasik Mukherjee in Bengaluru)
((Rajasik.Mukherjee@thomsonreuters.com))