For our Geo Quiz we're heading to Kenya's Rift Valley.
The lake we're looking for is not Kenya's biggest but it is one of the most economically important. Its waters and shores are home to fishermen, farmers and a huge cut flower industry.
The lake borders two national parks, and it's just 50 miles northwest of Nairobi … so it's a tourism mecca for Kenya.
And best of all it's home to a mix of wildlife including pink flamingos and hippopotamuses — or is it hippopotami?
So can you name this lake that was featured in the film version of "Out of Africa," about Danish writer Isak Dinesen.
It's called Lake Naivasha and sitting in a small boat on its water it looks like an African postcard. Giraffes nibble at acacia trees on shore, as flocks of birds soar by. Hippos peek above the water's surface, snorting and grunting.
The Lake Naivasha area attracts thousands of local and international tourists a year to its resorts, camps and two national parks and in the 1980"²s it attracted director Robert Redford as a location for his film "Out of Africa."
All that's part of the reason Naivasha is called Kenya's most economically important lake. But recently there's been trouble here as well, starting with its fluctuating water levels.
Emmanuel Odiambo gives boat tours on Naivasha. He says back in 2009 some areas were so shallow that he had to paddle tourists around with oars, so his boat's propeller wouldn't hit the bottom.
"The lake level was five meters deep. Normally it used to be twelve meters. "
The lake's water levels have always gone up and down. But many here blame some of the recent extremes on increasing human activity like farming. Pollution has increased as well. Forests in the watershed have been cleared for farms, increasing soil runoff into the lake. Fertilizer runoff has caused fish-killing algae blooms. Odiambo says that, a couple years ago, fish were dying in huge numbers and washing up on shore," Yeah, even we collect some fish, then we go and dig a small hole to dump all the fish in. Yeah, because I think when somebody sees a dead fish, that will cause a problem."
Scientists say a big part of the problem with water usage and pollution here comes from a single crop-flowers.
Flower cutter Peter Ojembo shows me his technique for cutting roses, which are grown in hundreds of green houses around Lake Naivasha, "You count the leaves — one two three — and then you cut from here."
He counts down from the head and snips the stem just above the soil. Ojembo cuts two hundred bundles of roses every day. Most of them are flown to markets in Europe.
Ojembo says he makes about seventy-five dollars a month, working six days a week, " The job is very hard. Because two hundred bundles per day, then the salary is very low."
But it's a decent job in this part of the world. That's why officials want to support the flower business while reducing its environmental impact. The Kenyan Wildlife Service is overseeing several programs to limit water use, and cut pollution. One of these, run by the World Wildlife Fund, is a pioneering effort in which downstream farmers pay upstream farms to keep their runoff clean. And there are signs that some of these are working.
Tour guide Emmanuel Odiambo says Naivasha looks way better thanit did just a few years ago. In 2009, he says he was on the verge of moving his business, " At that time, we were planning to take our boats to Lake Victoria. But then the water levels came back up. So, nowadays, no problem with the lake. "
The lake looks good again, and he isn't hiding dead fish from tourists anymore.