Around 64% of monitored lakes in pastoral landscapes are classed eutrophic or worse (Ballantinc and Davies-Colley, 2009, Land and Water Forum, 2010, Verburg et al., Similarly groundwater quality has been deteriorating, with one third of sites monitored between 1995 and 2008 showed increasing trends in nitrate levels (Daughney and Randall, 2009). Eutrophication can be defined simply as the increase in the rate of production and accumulation of organic carbon in excess of what an ecosystem is normally capable of processing. This can also reduce light penetration and lead to a loss of submerged aquatic vegetation.