Water is the second name of the life. The use of water includes agricultural, industrial, household, recreational and the environmental activities. The earth consists about two third of the water and only one third of the land. The earth consists 97.5% of salt water, 2.5% fresh water in which most of the water remains under ice in frozen condition and only 0.3% remains as the fresh water in form of river, spring, water etc.
The fresh water is a renewable source, yet the world's supply of clean and fresh water is steadily decreasing. Water demand already exceeds supply in many parts of the world. World population continues to rise at an unprecedented rate, many more areas are expected to experience this imbalance in near future.
The water is also considered as the resources because it is basic to all the living beings and the cornerstone of the civilization. The rivers, lakes, underground water, ocean are all water resources. It is considered as the renewable resources because of its hydrological cycle. There are about 6000 rivers and rivulets in our country. The estimation has shown that the total annual runoff from the territory of Nepal is 4877cm/sec. The rivers of Nepal are grouped into three major categories: The Karnali, the Gandaki, and the Koshi.
The lake in our country consists 2% to 3 % of water. The lakes are glacier lakes, tectonic lakes and the oxbow lakes which are Tilicho lake, Shey-phoksundo lake, Fewa lake, Rara lake, Ghoda ghodi taal, Nanda bhauju taal etc.
There are some hot springs known as Tatopani located on the sindhupalchok district as well as in Mugu district.
The rivers in Nepal are the white gold of Nepal and have the tremendous potentiality of generating hydro-electricity. Nepal has 2.27% of the world’s total estimated hydropower potential. Nepal has theoretically 83,000MW hydropower potential of which 40,000 is economically feasible. The average runoff volume is found to be 269,000m3.
The water in the river, lake, wetland, fall is known as surface water. The surface water is naturally filled up through precipitation and naturally lost through the discharge to the oceans, evaporation, and the subsurface seepage. Though the natural input to any surface water system is only the precipitation, within its watershed, the total quantity of water in that system at any given time is also dependent on many other factors. These factors include storage capacity in the lakes, wetlands, and the artificial reservoirs. The permeability of the soil, the runoff characteristics of the land in the watershed, the timing of the precipitation and the local evaporation rates. The proportion of the water lost depend on these factors.
The activities of the human can have the large impact on these factors. The humans use their ideas to increase storage capacity by constructing reservoirs and decrease it by draining wetlands. They increase runoff quantities and the velocities by paving the areas and channelizing the stream flow.
Sub-surface water or the ground water is the fresh water located in the space of the soil and the rocks or the water flowing within the aquifers below the water table is known as ground water. Sometimes it may be useful to make the distinction between the sub-surface water that is closely related to the surface water and the deep subsurface water is an aquifer.
Sub-surface water also has the inputs, outputs, and storage. Due to its slow rate of the turnover, sub- surface water storage is generally much larger compared to the inputs. The natural input to subsurface water is the seepage from the surface water whereas the natural output from the sub-surface water is the springs and the seepage to the oceans.
The water in the ground with its section is known as the aquifers. The precipitation in the form of the rain rolls down and comes to the aquifers. An aquifer is near to the equilibrium in its water content which depends on the grain sizes (permeability). The rate of the extraction may be limited by the poor permeability.
The water resources in Nepal are not eventually distributed so that we face the results during the seasons sometimes in the form of the drought and sometimes in the form of the flood.
In order to avoid the recurring drought during winter and the flood during the rainy seasons, it is necessary to conserve the flow during the high flood and utilize them during drought. The proper assessment and development of prevention can solve the scarce water resources condition of the country. Considering the facts in mind, the highest priority has been recorded to the development of water in the country during the last few decades.
Human is the member of the biotic community and as we continue our exploration of the geological cycle from the scale of minute communities of elements in soil, rocks and the regional patterns of the climate, geology-topography, the discoveries are about how these elements influence the incidence of the certain diseases and the death rates. The diseases are defined as an impala (Mahapatra) once resulting from the poor adjustment between an individual and the environment.
The climatic factors as temperature, humidity and the amount of the precipitation are sometimes intimately related to the disease pattern. Serious health hazards occur in the tropical region whereas the two of the worst climatically controlled diseases, Schistosomiasis called the shall fever is the significant cause of the death of the children. The malaria is clearly related to the climatic factors necessary to carry the diseases, i.e mosquitoes and snails are the climatically controlled disease.
The geological aspects of the environment must consider the cultural aspect as well which is associated with the patterns of the diseases and the death rates.
The high incidence of the stomach cancer in Japanese people is the relationship between culture and the disease. They prefer polished and powdered rice which contains asbestos as an impurity which is the cause of cancer in people. Hence, geology including cultural aspects and the climatic pattern is responsible for various diseases and the death.
Keller, E.A. Environmental Geology. Columbus, Ohio: Charles E. Miller Publishing Company, Bell and Howell Company, 1985.
Mahapatra, G.B. Textbook of Physical Geology. Shahadra,Delhi-110032: CBS Publishers and Distributers Pvt.Ltd., 1992.
T., Richard. Towards a Sustainable Future . India: PHI (p)Limited, 2008.