The biggest project we are handing off is the rainwater catchment pilot project. A rainwater catchment is a system of gutters and drainpipes connected to a collecting tank. Rainwater is one of the cleanest water sources available and can reduce or eliminate the need for family members to collect water from springs and rivers many miles away. If the system is properly maintained with roof and gutter cleanings, the homeowners may not have to boil the water to make it potable, saving the cost of firewood and the time required to heat the water. Rainwater catchment is a very attractive solution to the lack of clean water available in Kuria, Kenya but there are many issues we have to resolve to ensure the usability of the system. I'll run through our concerns and then describe our system.
The largest factor in the success of a rainwater catchment system is, as you probably guessed, rainwater. Kuria, Kenya suffers from one long drought period from June to August as well as a few other dry months, February, November, and December. These dry periods of very little and sporadic rain are a real challenge for designing rainwater catchment systems. Buying or building tanks with large enough storage to make it through these droughts is cost prohibitive so sizing tanks becomes a game of balancing cost with usability. If we spend too little and get a tank to small, the system may only be useful for 30% of the year, only on days that it rains making the system virtually useless. If we spend too much and get a large tank, the farmers will not be able to afford buying the materials in the first place. Unfortunately, we have very little information on rainfall patterns, we only have 24 months of total monthly rainfall data which doesn't give us the daily rainfall picture we need to make proper judgements.
The second factor is operation and maintenance. The rainwater catchment itself is pretty simple but it requires quite a bit of effort from the homeowner to work properly. If the homeowner neglects the system, the gutters and downspouts will get clogged, gutters will leak, and dirty water will make it into the tank. Contamination can also come in the form of runoff from the homeowners courtyards as the courtyards are generally filled with animal excrement from corralling the animals at night for protection. Developing a rainwater catchment system with minimal maintenance and training the homeowners on how to perform the maintenance are two important things we must do to provide a sustainable solution.
Cost is the final factor for design. We must reach a cost point that allows farmers to pay for the entire system without subsidies from Nuru. Initially, Nuru will cover the full cost for the six w+s leaders and the 42 w+s representatives so that their systems can be models their neighbors can learn from. When the program is rolled out to the larger community, Nuru may cost share the materials but we will eventually place the full cost of the system on the farmer. By designing a system that the farmers can afford we will encourage the organic growth of the rainwater catchment adoption.
Organic growth is a top priority at Nuru. We will be leaving Kuria, Kenya within 5 years of arriving in September 2008 so if our programs are not designed to continue without our presence, they will fail. We are here to give Kuria, Kenya a jump start and not fall in to the trap of dependance that has plagued other NGO's. That is a big reason for community empowerment and why my Kenyan w+s counterpart Lucas has a much more important role in the community than I do. I'm more of a behind the scenes advisor handling the technicalities and filling in where Lucas needs help. One of those technicalities is the rainwater catchment system design.
I have been working with Nicole for the better part of two months hammering down a rainwater catchment design for Kuria, Kenya based on the typical local compound and material availability.
Our final design for the pilot consists of a 1000 L tank placed on top of a brick foundation with iron gutters flowing into a drain box which then flows into a first flush device and then the tank. Most of the design is straightforward and easily understandable, all except the first flush device. A first flush system is a device that collects the initial 1-2 mm of rainfall on the roof and diverts it from the main storage tank. Maybe you're thinking why we would waste such a precious resource but if your consider the contaminate build up on the roofs and in the gutters between rainfall you would realize the need for a first flush device. The initial rainfall collects all of the dirt, dust, and debris from the roof and gutters and is highly contaminated with everything from bugs to bird droppings. By diverting it from the main storage tank we ensure the quality of the rainfall collected. Amazingly, studies have been performed showing that this initial rainfall is the only portion of the water collected that is contaminated so once this rainfall is diverted, the remaining rainfall is almost perfectly clean.
Our first flush device is part of the drainage system from the gutters to the tank. The gutters flow into a box we call the drain box that has a metal screen on the bottom to catch large debris from the roof. This box connects to a PVC pipe that flows into the main storage tank. Before the PVC pipe flows into the tank a T elbow splits the flow into our first flush device. The PVC pipe flows roughly horizontal from the drain box and our T elbow sits just in front of the tank with the leg of the T facing down towards the ground. To this, we attach another length of PVC pipe and cap the end which provides a known volume. In order for rainfall to make it into the large storage tank, this length of PVC pipe will have to be full so that the rainfall will no longer flow down the leg of the T and will instead flow out of the other side of the cross of the T and into the main storage tank. The known volume in the PVC pipe at the leg of the T will be calculated to capture the first 1-2 mm of rainfall and hence all of the contamination. At the end of the rainfall, the homeowner will unscrew the cap of the first flush device and drain out all of the dirty water so that the system can function properly for the next rainfall. This type of first flush device has been used widely in Thailand with great success and was featured in one of our design resources, Rainwater Catchment Systems for Domestic Supply: Design, Construction and Implementation by Erik Nissen-Petersen and John Gould.
The rest of the design is fairly simple, just gutters into a box and a big tank with a brass tap. These first six rainwater catchments we will be installing are part of our pilot program to check if rainwater catchment systems are the way to go to provide safe drinking water for the community. We will be testing out all of our concerns and collecting all sorts of data including highly accurate daily rainfall data from a USGS rain gauge so that we can correlate tank volumes with rainfall data. Best case we find our system works well and it is usable for the majority of the year. Worst case we find out that rainwater catchments are too expensive for the use they provide. The middle of the road and most likely case is that we will have to improve our system but have found that in general it is very useful to the homeowners.
This week we will be getting the materials we purchased last week and will begin construction of our first rainwater catchment system on the home of one of our leaders, Marabe. The six leaders will come to assist with construction and help us adjust the system as we are installing it. We will then move on to the next five homes and hopefully finish all six within three weeks. There will then be a long period of data collection so that we can evaluate the systems. After crunching our data and redesigning we will implement our new and improved design on the original 42 w+s representatives plus about 50 new representatives from a second recruitment drive. We are shooting for early 2010.
After we have 100+ examples in the community we will move to the more organic phase of the program where farmers will take out loans to install the rainwater catchments on their homes, paying them back after harvests. We have established a Community Development Committee (CDC) in Kuria, Kenya that will continue all Nuru programs upon our departure. Lucas, my w+s counterpart is one of the members of the CDC and is moving toward the independence and responsibility that will be required of him when Nuru moves out of Kuria, Kenya in just over four years. We have been working on other revenue generating programs for the CDC such as the farm loans in order to ensure it's sustainability without western funding. Nuru will maintain a connection with the CDC in Kuria, Kenya but we will only be checking in. When we leave, Nuru is the community.
As a final thought I would just like to bring up one of the largest reasons we are so concerned with bringing clean water to the families of our community. The vast majority of people collecting water for families are school age girls. Their water collection duties are difficult and in some cases make going to school regularly impossible. This is especially true when they have to hike and queue for hours during droughts because most of the nearby springs dry up forcing the community to migrate to the deeper springs. Obviously this cripples the education of these young woman and thereby their empowerment.
Kuria, Kenya is a patriarchal community but many powerful women are becoming leaders in the community. It has been shown that the number one most important factor to making communities grow and bringing them out of poverty is the empowerment of women. It is an issue we as westerners cannot take on head first because we will be looked upon as forcing western ideas on people we don't fully understand. But, we can give girls and young women every opportunity to empower themselves with programs such as the rainwater catchment that eliminates the need for them to work hours everyday just to provide clean water for their families.
Even from my personal experience of being surrounded by strong women, my mother especially, I know how much of an impact they can have on a family and community. Women have a way of fighting tooth and nail for their children so that even if they are dealt a raw hand, they can still prosper. Empowered women fighting on behalf of their children and community are a force of nature to be reckoned with.
twenty-two new pictures
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