around the world. chemicals leaching into the water are causing blooms of toxic algae that >> brad: a dying lakes polluted by progress, a problem in alberta and around the world. chemicals leeching into the water are causing blooms of toxic algae that upset entire ecosystems but a team from the university of alberta, they say they may hold the key to helping nurse those lakes back to healthed a richard zara shows us. >> reporter: that's lindsay pulling the sled. we are fought on lake nakamun northwest of edmonton. they are part of aniversity of alberta study on water quality. today they are collecting samples from the lake's bottom. nathan, a masters student in earth and atmospheric sciences is drill a hole. >> basically like a shower curtain that goes from the surface of the water down into the sediment so it's exposed to the airs and the sediment but not the lake. >> reporter: the health of many lakes is in jeopardy. the problem isuitiryfication. too many institute presents, phosphorous especially coming into the water. it comes from humans. >> that causes really gross, terrible water quality problems. we get lot ls of algae and bad odour and taste to the lake and you see kind of green scum on the nor lines. >> reporter: that green scum is toxic, potentially deadly blue-green algae. it thrives on those forrus and dies and decomposes and robs oxygen from the water cut offing the labour's life support system. so this experiment asks: is there a way to lock that phosphorous up in the sediment be starve off the algae and give the lake a chance to heal itself? >> so we have added iron to these enclosures. >> reporter: they poured different concentrations of iron. it chemically interacts with the phosphorous turning it into a mineral that falls to the bottom. >> so this is a sediment core. this is the tube that will be collecting the core with. is it going to work? okay. i feel like i'm in the sediment. >> if you feel you're in it, yeah. >> okay. >> reporter: but it's not magic bullet. lindsey believes the key is to stop flooding the lake with more nutrients in the first place. >> so plugging the bottom so we can keep the sediments in the core. >> reporter: these core samples will be sent back to the lab to measure the interaction between the lake bed and the water above and proved the year-long experiment worked but dumping iron in the water all ters the ph which impacts other parts of the ecosystem. >> thank you. >> reporter: so lindsay's testing for that too with a dredge. >> so it's open and then we drop this trigger mechanism which closes it and grabs a sample of mud. >> reporter: and it's what's inside that counts. >> why do we care about the bugs? >> why do we care about the bugs? because you need bugs for the ecosystem to live, so the fish can feed and if every invertebrates were killed off you wouldn't have anything in your lakes. >> reporter: lindsey predicts that over the coming decade water will become one of the biggest issues we have to face individually and globally. >> i think water quantity is going to be an issue, especially with climate change but water quality, i think, to me is more important because we just keep contaminating -- the little amount of fresh water that we have. >> richard oz row, ctv news. >> brad: so that's what's happening in the water. and on the land. let's see what's going on in the air right now. we have ctv's mark driesschen standing by with your national forecast. marke? >> marke: thanks very much. hope you are enjoying injury sunday. let's check out the weather on the west coast. increasing cloud through vancouver and victoria. good chance of showers later on in the day. same thing for the interior through prince george. 9° there. up to the north showers for whitehorse. moving into alberta, clouding over in edmonton and kind of a mix of sun and cloud through calgary tomorrow. 14 and 15°. beautiful day for you in saskatchewan. nice and sunny, 16 in saskatoon. also 16 in regina.