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Implementation of a large scale rainwater harvesting project using the roof of Tabora cathedral in Tanzania

The cathedral has a large roof and using average rainfall data between 1894 and 1990 from worldclimate.com and a run-off co-efficient of 0.85 around 500'000 litres could be collected in a year. Using a rationing method this gives a storage requirement of approx 200'000 litres to supply around 1360 litres per day. Given the significant size of this project and in want of more information regarding the performance of the guttering in heavy rain the goal is perhaps to provide 100’000 litres of storage. The cathedral has 8 down pipes so current thinking is between multiple below ground plastic tanks at all 8 locations with a moveable pump or one or two very large below ground/partially below ground ferrocement tanks with appropriate guttering. So here are some initial questions which I would be grateful for your advice on. 1. What is your opinion on the two schemes? 2. Do you have any specific construction advice given that the area may experience some seismic tremors on an irregular basis? 3. Can you suggest available and reliable pumps for each scheme? 4. Is a mutely-tank/moveable pump design a viable one, have similar designs been done, what might access to the individual tanks look like?

Implementation of a large scale rainwater harvesting project using the roof of Tabora cathedral in Tanzania

The cathedral has a large roof and using average rainfall data between 1894 and 1990 from worldclimate.com and a run-off co-efficient of 0.85 around 500'000 litres could be collected in a year. Using a rationing method this gives a storage requirement of approx 200'000 litres to supply around 1360 litres per day. Given the significant size of this project and in want of more information regarding the performance of the guttering in heavy rain the goal is perhaps to provide 100’000 litres of storage. The cathedral has 8 down pipes so current thinking is between multiple below ground plastic tanks at all 8 locations with a moveable pump or one or two very large below ground/partially below ground ferrocement tanks with appropriate guttering. So here are some initial questions which I would be grateful for your advice on. 1. What is your opinion on the two schemes? 2. Do you have any specific construction advice given that the area may experience some seismic tremors on an irregular basis? 3. Can you suggest available and reliable pumps for each scheme? 4. Is a mutely-tank/moveable pump design a viable one, have similar designs been done, what might access to the individual tanks look like?