In the development of industrial facilities and business operations, a stable water supply becomes an essential element, as it supports smooth production and keeps distribution well-controlled.
This is where the role of water reservoirs becomes important. This water infrastructure is not just an ordinary storage facility, but also supports utility management efficiency and business expansion. To better understand the types of water reservoirs and how they are constructed, read the complete explanation here.
What Is a Water Reservoir?
A water reservoir is an artificial structure designed to collect and store large volumes of water in order to improve water security for communities. This structure may take the form of a dam built on a natural water body or an artificial basin in lowland areas filled by rainwater or diverted river flows.
Water reservoirs are an important part of the water supply system in various countries, especially in areas with long dry seasons and unpredictable rainfall.
During prolonged droughts, water stored in the reservoir is gradually released to meet public needs, such as providing drinking water and supporting industrial operations. Conversely, during high water flow, the reservoir can store water reserves and reduce the risk of flooding.
Types of Water Reservoirs
Based on their location relative to the river flow, water reservoirs are divided into two types:
1. On-Stream Reservoir
An on-stream reservoir or impoundment is a reservoir formed when a dam is built across a river. Its size is relatively large and most commonly used. An example of an on-stream reservoir is Lake Diefenbaker in Saskatchewan, Canada.
2. Off-Stream Reservoir
In contrast to the previous type, an off-stream reservoir is not located directly in the river's flow path. This means that the reservoir area is separated from the main river.
An off-stream reservoir is formed using dikes or waterproof walls that surround part or all of the reservoir area. One example is the Springbank Off-Stream Reservoir in Alberta, Canada.
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How to Make a Water Reservoir
It is necessary to understand that the location of a water reservoir must meet several criteria. First, there must be an adequate water source, which can come from rivers, rainfall, or watershed flows.
Second, environmental impacts must be minimized, such as the relocation of residents and changes to the ecosystem. Third, the site must have enough space and be located at an appropriate elevation to ensure smooth water flow and more efficient distribution.
If all three are met, the process of building a water reservoir will go through the following stages:
1. Diversion of Water Flow
The first stage in building a reservoir is actually the construction of a dam that functions to hold back the flow of water and create a reservoir area.
However, to build a dam, water flows, such as rivers or tributaries, need to be temporarily diverted. The purpose is to create a dry construction area and facilitate engineering work.
Nevertheless, for large rivers, a total diversion is usually not possible. Instead, only part of the river is dried and used for construction, while water continues flowing through the remaining section. This process is repeated section by section until the entire dam structure is completed.
2. Dam Foundation Construction
At this stage, there is a difference between on-stream and off-stream reservoirs. In on-stream reservoirs, the new foundation is prepared after the river is diverted. As for off-stream reservoirs, the foundation can be prepared immediately.
This stage begins with excavating the foundation to remove soft soil, mud, sediment, plant roots, and vegetation. Excavation is carried out until bedrock is reached, which is the natural hard rock layer underground. Since the bedrock structure is stable and can reduce the risk of soil settlement, the foundation must be placed directly on it.
If the dam uses the valley walls as part of its structure, any unstable parts of the walls must be removed to ensure the rock is truly strong, rigid, and resistant to water seepage.
Once the bedrock is exposed, an inspection should be conducted to look for fractures and cavities. If small cavities are found, they can be filled with grout, which is a mixture of liquid cement injected into the rock gaps. Meanwhile, if there are large cavities, they can be filled with concrete.
Both methods are carried out to strengthen the rock and block water seepage paths. Next, the dam foundation surface is moistened and compacted using rollers.
In a Hydroelectric Power Plant (PLTA) dam, there is often an intake tower, which is a tower used to control the water supply. If there is an intake tower, it is necessary to install rock bolts underneath it and construct a large concrete foundation.
Rock bolts are long steel rods that are embedded into the rock and function to anchor the structure to the bedrock so that it does not shift.
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3. Installation of Dam Concrete Walls
After the foundation has been completed, the concrete walls of the dam can begin to be installed. The concrete walls function to withstand the pressure of the reservoir water and control the flow of water.
Next, the walls are coated with a protective layer to prevent damage. The coating must have high adhesion, allow water vapor to escape from the concrete, be able to withstand high water pressure, and resist chemical content in the water.
Generally, the coatings used are made from acrylic, epoxy, polyurethane, or crystalline waterproofing materials.
4. Restoration of Water Flow
After all the dam structures are installed, the area that will later be flooded must first be inspected to ensure that there is nothing that could potentially contaminate the water, such as trash or debris.
Once the area is confirmed to be clean, the water flow can be redirected back into the reservoir. In on-stream reservoirs, water usually begins to accumulate naturally behind the dam. Meanwhile, in off-stream reservoirs, water must be diverted, pumped, or channeled through pipelines.
Entrust Industrial Water Treatment to Chandra Daya Investasi!
Raw water must undergo processing first in order to be suitable for use. Chandra Daya Investasi, through its affiliated company, Krakatau Tirta Industri (KTI), offers clean water treatment solutions that are suitable for application in manufacturing processes.
With decades of operational experience, KTI has been widely trusted in supplying clean water for various industrial needs. KTI's clean water treatment units utilize water sources from the Cidanau River, Cipasauran River, and Nadra Krenceng Reservoir.
To process water from these sources, KTI operates the Krenceng and Cidanau Water Treatment Plants (WTP). The Krenceng WTP has a capacity of 1,800 liters per second. Meanwhile, the Cidanau WTP has three intake pump units, each with a capacity of 600 liters per second.
So, interested in processing water from reservoirs for your company's needs? Entrust your industrial clean water reservoir processing needs to Krakatau Tirta Industri and Chandra Daya Investasi as #YourGrowthPartner.
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