Water Resources Development Potential

Water is one of the natural resources that has a very important function for life and the life of all living things on this earth, including. Life begins or originates from water, all life will continue to grow and develop. Without water, all life processes will not take place, so the availability of water is an important element in life. As well as providing raw water, irrigation and industrial water, etc., this is a main concern and priority. Water is a human right; meaning, every human being on this earth has the same basic rights to use water, in accordance with the use of water guaranteed by the 1945 Constitution of the Republic of Indonesia.

Potential of Water Resources

Potential water resources can come from several sources, such as surface water, river water, lakes, reservoirs, swamp and beach water and sea water. Based on the place of origin, water resource potential is divided into 2, namely surface water resource potential and ground water resource potential. Surface water is water found on the surface of the earth. Meanwhile ground water is the amount of water stored in the soil layers, where the water is stored in the soil layers after the surface water moves through the aeration zone and is retained by capillary forces in the soil pores.

Potential surface water resources

Surface water resources are all types of water that are on the surface of the earth. This type of water resources can be seen visually, such as sea water, river water, reservoir water or lakes. As previously explained, of the total amount of water on the earth’s surface, 97% is in the form of oceans, 2.7% is in the form of icebergs, both at the North and South Poles as well as groundwater content, and the remaining 0.3% is water that is in d] rivers, reservoirs or lakes. 0.3% of surface water is cyclic water. Namely having a cycle with a circular pattern (KBBI – 2018). For more details, see the hydrological cycle in the image below.

Figure The Hydrological Cycle

Source : poros ilmu.com (2017)

In the picture above you can see a cycle that begins with the condition of evapotranspiration (evaporation, infiltration and transpiration) of surface water in various sources. Which evapotranspiration is the evaporation of water until it collects in the atmosphere. This evapotranspiration causes the formation of clouds which are collections of water vapor at a certain height. These clouds will eventually turn into very small ice particles which is called the condensation process. The more ice particles that are formed, the bigger the cloud that will form with a darker black color. These ice particles can move horizontally due to wind pressure in the atmosphere, which is called an advection event.

If afterwards there is a change in temperature around the cloud, the ice particles that form the cloud will melt again and fall from the atmosphere in the form of rain or snow. This event is called precipitation. This series of events repeats continuously in a regular sequence and is known as the hydrological cycle. In general, this hydrological cycle can be seen in the scheme (flow chart) below.

Schematic Image of the Hydrological Cycle

Source : Belajar Kurikulum 2013

In this hydrological cycle, not all the water that evaporates will return to surface water. Some of the water that returns in the form of rain will experience infiltration, namely the condition where water is absorbed by the pores of the soil when the rainwater goes through a run-off process, namely the process of flowing water from high places to lower places.

This process is what occurs when rain or snow falls on the plateau, where the water will flow through rivers, creeks or other channels that occur naturally or artificially so that the water will return to the oceans. This infiltration will ultimately accumulate a certain amount of water in certain soil layers which will later become groundwater.

Potential groundwater resources

As explained in the previous discussion, the infiltration process will cause some surface water to seep into the soil through the pores in the soil layer. This water seeps through the permeable layer of the soil, namely the layer that water can easily pass through and is known as an aquifer. Infiltration through this aquifer will continue to increase and move until it reaches the impermeable layer on the ground and collects in that layer and is known as groundwater.

Groundwater is one of the water resources besides surface water (rivers, reservoirs, lakes and rainwater). Groundwater plays an important role, especially in maintaining the balance and availability of raw materials for household or industrial purposes.

Images of Groundwater and Surface Water

Based on the origin and process of occurrence, there are several types of groundwater, namely:

Meteoric Water or Vados Water is groundwater that comes from rain that seeps into the ground.
Fossil Water or Connate Water is ground water that is trapped in the pores of rocks when the rocks are formed. Ground water can come from fresh or sea water which is high in minerals.
Fossil Water or Connate Water is ground water that is trapped in the pores of rocks when the rocks are formed. Ground water can come from fresh or sea water which is high in minerals.
Shallow groundwater or shallow groundwater is groundwater that is found above the impermeable soil layer and close to the earth’s surface. For example: Rivers, lakes, wells, swamps etc. And,
Deep ground water is ground water that is found in the layer between two impermeable layers. For example: artesian water sources whose water comes from underground water.