Plumbing for varied water systems

The kind of plumbing you choose to have in your home is often determined by the source of water. If it is a far-flung upcountry area where there are no reliable water connections yet, you are most likely to rely on underground pumped water from a borehole or harvested rainwater. The most important aspect, then, is how well to plumb for the system you have chosen in order for it to serve its purpose.

For instance, when Charles Byamugisha was building his upcountry home in 2001, the only reliable sources of water at the time were wells that were shared by domestic animals. Byamugisha says he built his house in the middle of a hill yet the well lay ain the valley, a distance he thought would be unbearable for his family. 

“All the roof gutters were positioned on the house faceboard directing all the water in one direction. I did not want to see a water droplet put to waste during the rainy season because some dry spells last longer than expected. The fact that the house is on a hilly terrain made water flow easy without water stagnating in the gutters,” Byamugisha says.

After directing the water to one collection point, the task at hand for Byamugisha was to build a water tank that could contain the large amount of water from all the roofs, including the four- roomed servants’ quarters. He recalls that his plumbers did not only dig approximately 10 feet deep to gain a strong and stable foundation for the water tank but that they also had to build 15 feet upwards using clay bricks to have an elevated water tank.

“I wanted the tank to have two water collection points; one inside the perimeter wall for use when the tank is full and the second outside the perimeter wall when the water levels have fallen below the interior fetching point,” Byamugisha recalls.

However, having a water tank whose height is 25 feet, Byamugisha says, comes at a cost. For instance, the tank alone consumed more than 30 bags of cement, approximately three trips of clay bricks because the tank had to be given a strong thick body, and approximately six trips of sand for plastering the interior and exterior of the tank to leave no room for any leakages.

Twenty years later, Byamugisha says his home never runs out of water during the dry season. When the water wells are completely dry, Byamugisha resorts to the water tank as a source of water for his domestic animals. The tank can hold water enough to last for about four months  in a drought.

Unlike Byamugisha whose home relies on rainwater, Emmanuel Opio says the house he is constructing in Kawanda has two water plumbing systems; piped water from national water lines as well as rainwater. However, much as the piped water system is already complete, with all the required plumbing built within the wall, the focus is on plumbing for rainwater whose storage tank is being built underground. 

“I want the underground water tank far from the house because I want my big compound free from any visible built structures to keep its beauty. It will serve as an emergency source of water should there be need. The tank water will also be used for watering flowers, trees and external house chores such as washing cars and watering the compound because I love a green environment,”Opio explains.

Patrick Mugerwa, a plumber says when planning for a rainwater system, if the water tank is to be built underground especially at the edge of a big compound like Opio’s, the water pipes should also be buried underground and not held with metallic poles flying over the compound to kill its green beauty. These underground pipes should however be built with manholes especially when the pipes are collecting water from different roofs facing different directions. 

“When you do not use water manholes, it makes repair of a broken or clogged underground pipe difficult. With manholes, the process is less hectic compared to when you have to dig up a long conjoined pipe or system to identify a broken spot,” Mugerwa explains.

With rainwater harvesting, the main source of dirt that normally blocks the plumbing system, Mugerwa adds, is dust, bird and rat droppings. It may also be grass and stick from nests that birds build in the roof gutters during long dry spells. In worst case scenarios, it could be rat carcasses that block the system.

“When it rains after a long time, the dust flows into the water tank, settles at the base and turns into mud. Some of the dust remains in the pipe system and solidifies and never reaches the tank. Over time, this mud accumulates and builds up in the system, blocking it. It becomes easy to unblock a clogged system when you can trace the dirt through the manhole,” Mugerwa explains. 

Byamugisha agrees with Mugerwa, advising that since most, if not all, underground water tanks gather the water from the roof and have wide openings especially on top, it is recommended to drain all the water from the tank at least once or twice a year and clean the tank thoroughly. This is also necessary because tank water, regardless of where it is stored underground stays stagnant for long and tends to develop a weird smell, making it hard to use.    

“If you do not have a water pump to get rid of old water in the tank, you can scoop it out manually using buckets,” Mugerwa advises.

The second clean rainwater harvesting measure, Byamugisha says, is placing a strong sieve at the extreme end of the pipes that collect water from the roof gutters so that the dirt therein is easily trapped, and regularly removed every time it rains before it becomes so heavy as to break the sieve and get into the tank. 

Different plumbing systems

Gerald Kasimba, a plumber says it is not advisable to have different water sources sharing the same plumbing systems. For example, the national water system always has treated water whereas water, say, pumped from underground is not treated.

“You can have two different water systems in the same house but have them structured or laid to serve different purposes. You could use water pumped from underground for external chores such as cleaning the house or washing cars and gardening and use the one for national water grid for healthier purposes such as cooking and boiling,” Kasimba explains.

If you choose to have two water systems, Kasima urges that you not only use different pipes to supply water where you need it but also have different storage facilities. One water storage tank cannot be served by two different water systems at a go.

“It is just like you would have different switches for solar power and hydroelectric power. A tank that stores underground pumped water cannot be used to store national water because the water from two grids serves different purposes. Water from underground can be connected to the toilets for flushing and to the exterior tap for cleaning while that from national water can be connected to the interior kitchen for cooking,” Kasimba explains.

Unlike Byamugisha and Opio whose rainwater tanks are built underground, Kasimba advocates for a raised storage tank because it is easier to clean and monitor especially at the base. You can, however, have two rainwater storage tanks with a water pump to draw water from the underground tank into the raised one. 

Plumbing on top of wall surfaces

Sometimes you may have no choice but to have your plumbing system fitted outside the wall surface. This happens when you did not envisage, at the time of building your home, certain water systems such as national water reaching your area and yet later realise you need both systems in the house. 

In such a case, Kasimba recommends using polypropylene random pipes (PPR) that are stronger and rigid to withstand any weather and temperature conditions under any severe circumstances. However, you have to safeguard them from children as well as animals such as goats that may break them.  “But if your area already has national water connections, it is better to have the pipes built within the wall body because they will be safer and will live as long as the house exists. The house will look more beautiful when pipes are built within the wall compared to when they are built protruding out of the wall,” Kasimba concludes.