damaged an important wetland ecosystem, they also had a significant impact three hours drive away in kigali, the capital city. the water that pours from the marshlands is a vital source of hydro power for rwanda's capital. as the wetlands began to dry out, power stations below couldn't generate enough electricity. the rwandan government rented diesel-powered generators to make up the shortfall. doctor rose mukankomeje took me to see them. >> so what is happening here is that those generators... we are renting them from this company, and we are being obliged to rent them, especially, when we degraded the wetlands and we lost 20 megawatts of electricity, and to run those machines we are paying 65,000 u.s. dollars a day. >> $65,000 a day, that's multimillions of dollars per year. >> yes, it millions of dollars and, as you must--might know, rwanda is not a rich country. some of that money has been borrowed from the bank, as from taxpayers. >> how does this affect the climate? >> of course, those machines, they run on diesel, and when you're burning diesel, you are producing greenhouse gases. >>