drop in ththe ocean, sayays marn taylor. he sees justnene answeto t the crisis, anand it has ecoconomic consequencnces. martin: less dairy? i mean yes, it does mean less dairy. it means l less cows, less mil, and d maybe farmrmers having t o switchch to somethining els. but that's the way it is. they've gogot to accept t that. now jujust because some people e mamaking money, , doesn't meanl the rest of usus should havevo puput up with a a poisoned environment. reporter: : by 2040, the vernment wants 9 of alalnew zealanwawaterso be c can enouough tswim i in. step o o on their r list, lowerg standards, with instant result overght,t, watways h havbecome draticallyleaner. at least on paper. host: each year around four million tons of cocoa are harvested worldwide. a third comes from ivory coast in west africa, and other big producers are ghana, indonesia, nigeria, and ecuador. the cocoa tree is native to central amererica. and that's s still home toto e world's oldest and rarest cocoa variety. we visit a small plantation in west

for year the powerful milk lobbhas s pushed envirironmentl activiststs aside, sayays marn taylor.. pure, crystatal-clear teter hs lo been n ered a aational eaeasure, something ne zealanders are pudud of or were. martrtin: everyonene sayw zealand's 100% pure. no, nono, we've 100%0% failed. we've e let the situtuation ha. and itit hasn't justst bn the la nine years o of a nationalal government, it w was the previs labourur gnment as well.l. reporterer: steppes asas far ae eye can see. much of the canterbury region once looked like this. bubut things have chananged. exextense irirrigaon systetems provide ththwater necessary for luscious g grass to grgrow - pastures for more cows. the water is taken from the rivers, leaving them more vulnerable to environmental damage. ryan o'sullivan says there is nothing wrong withth using the water fofor irrigationon. ryan: as soon as that water hits thoceaean, is wortrthls. so it only m makes sense f fore ececonomic well-l-being of a c y toto utilize thahat water fr econonomic gain. reporter: he says wherththere is grs, theheres less g gund erosion