Monday
Arrive in Arusha in northern Tanzania to conduct a survey of high mountain forest catchments in an area suffering from a two-year drought. Meet with Richard Minja, a long-time colleague. Discuss locations for our fieldwork. It looks as though the north is out of bounds due to recent bandit activity, but it is very drought-stricken and a place we need to visit.
Tuesday
Walk up Monduli mountain to inspect the water source for Monduli town. We dodge a herd of Cape buffalo and pass by a rotting zebra haunch hung in a tree to attract leopards for tourists on hunting holidays. The hunting company helps surrounding Masai villagers by piping water from high springs to tanks below. Villagers walk up to 20km to get water. Climbing the 2,000m mountain works up a thirst. Drop in to a bar for a beer and roast meat.
Wednesday
By a dried-out river bed, the village of Fereji ("a ditch") has its water piped down from a stream on the mountain. There is a school and a clinic - we chat to the teacher and the doctor. We find a group of schoolchildren queueing by the car and give them a lift, saving them a 10km walk to their bomas in the bush.
Thursday
Head for Mto-wa-mbu ("mosquito river") next to the Manyara National Park. While everywhere else suffers from a drought, here there are groundwater springs, fed by the nearby Ngorongoro highlands, and irrigated agriculture. The Masai cannot get cattle here because of crops and the national park. On the way back to Losiminguri, a crowd of about 200 Masai wait around the end of the pipeline that comes from a mountain spring 5km away. A group of Moran, the red-cloaked warrior age-set, regulate access to the trickle of water. Each village can come every second day.
Friday
Head north to a water source in the forest. Our local guide tells us more about the ravages of the bandits. Apparently, they were a well-armed renegade Somali rebel faction and had a pitched battle with the army. At the base of Longido mountain, there are some traditional wells at Kimokouwa ("place of the old men") next to the washed-out earth dam. Here, the Moran pass buckets of muddy water from wells to troughs. Each herd of several hundred cattle is watered every two days.
Saturday
Dawn. Drive past more dried-up, abandoned dams. The road winds out of the arid plains high onto the mountain's shoulder and through verdant montane forest. The Moran update me on the latest European football results. After visiting their boma for tea, we watch rainstorms sweep across the plain, the first for two years. The end of the drought finds us lying on our backs in the pouring mud changing a wheel.
Sunday
Fly back to York and am met by very wet weather.
Jon Lovett is senior lecturer in environmental management, University of York.