WATER CONSERVATION

What is water conservation.?

Water conservation is the practice of using water efficiently to reduce unnecessary water usage. According to Fresh Water Watch, water conservation is important because fresh clean water is a limited resource, as well as a costly one. As a homeowner, you’re probably already well aware of the financial costs of inefficient water use. Conservation of this natural resource is critical for the environment — and our wallets

Water conservation includes all the policies, strategies and activities to sustainably manage the natural resource of fresh water, to protect the hydrosphere, and to meet the current and future human demand (thus avoiding water scarcity). Population, household size and growth and affluence all affect how much water is used. Factors such as climate change have increased pressures on natural water resources especially in manufacturing and agricultural irrigation. Many countries have already implemented policies aimed at water conservation, with much success. The key activities to conserve water are as follows: any beneficial reduction in water loss, use and waste of resources, avoiding any damage to water quality; and improving water management practices that reduce the use or enhance the beneficial use of water. Technology solutions exist for households, commercial and agricultural applications. Water conservation programs involved in social solutions are typically initiated at the local level, by either municipal water utilities or regional governments. Common strategies include public outreach campaigns, tiered water rates (charging progressively higher prices as water use increases), or restrictions on outdoor water use such as lawn watering and car washing.

RESERVOIRS

A reservoir from French is an enlarged lake behind a dam. Such a dam may be either artificial, built to store fresh water or it may be a natural formation.

Reservoirs can be created in a number of ways, including controlling a watercourse that drains an existing body of water, interrupting a watercourse to form an embayment within it, through excavation, or building any number of retaining walls or levees.

In other contexts, "reservoirs" may refer to storage spaces for various fluids; they may hold liquids or gases, including hydrocarbons. Tank reservoirs store these in ground-level, elevated, or buried tanks. Tank reservoirs for water are also called cisterns. Most underground reservoirs are used to store liquids, principally either water or petroleum

WATER RESERVOIR DAVANAGERE

Types of Reservoirs

i . Dammed Reservoirs

Dammed reservoirs are artificial lakes created and controlled by a dam constructed across a valley, and rely on the natural topography to provide most of the basin of the reservoir. These reservoirs can either be on-stream reservoirs, which are located on the original streambed of the downstream river and are filled by creeks, rivers or rainwater that runs off the surrounding forested catchments; or off-stream reservoirs, which receive diverted water from a nearby stream or aqueduct/pipelined water from other on-stream reservoirs.

Dams are typically located at a narrow part of a downstream of a natural basin. The valley sides act as natural walls, with the dam located at the narrowest practical point to provide strength and the lowest cost of construction. In many reservoir construction projects, people have to be moved and re-housed, historical artifacts moved or rare environments relocated. Examples include the temples of Abu Simbel (which were moved before the construction of the Aswan Dam to create Lake Nasser from the Nile in Egypt), the relocation of the village of Capel Celyn during the construction of Llyn Celyn,and the relocation of Borgo San Pietro of Petrella Salto during the construction of Lake Salto.[citation needed]

Construction of a dammed reservoir will usually need the river to be diverted during part of the build, often through a temporary tunnel or by-pass channel.

In hilly regions, reservoirs are often constructed by enlarging existing lakes. Sometimes in such reservoirs, the new top water level exceeds the watershed height on one or more of the feeder streams such as at Llyn Clywedog in Mid Wales. In such cases additional side dams are required to contain the reservoir.

Where the topography is poorly suited to a single large reservoir, a number of smaller reservoirs may be constructed in a chain, as in the River Taff valley where the Llwyn-on, Cantref and Beacons Reservoirs form a chain up the valley.

DB Dam near Davanagere

TB Dam ,Hospete

ii. Coastal reservoir

Coastal reservoirs are fresh water storage reservoirs located on the sea coast near the river mouth to store the flood water of a river.[6] As the land-based reservoir construction is fraught with substantial land submergence, coastal reservoir is preferred economically and technically since it does not use scarce land area.[7] Many coastal reservoirs were constructed in Asia and Europe. Saemanguem in South Korea, Marina Barrage in Singapore, Qingcaosha in China, and Plover Cove in Hong Kong, are a few existing coastal reservoirs

iii. Bank-side

Where water is pumped or siphoned from a river of variable quality or size, bank-side reservoirs may be built to store the water. Such reservoirs are usually formed partly by excavation and partly by building a complete encircling bund or embankment, which may exceed 6 km (4 miles) in circumference. Both the floor of the reservoir and the bund must have an impermeable lining or core: initially these were often made of puddled clay, but this has generally been superseded by the modern use of rolled clay. The water stored in such reservoirs may stay there for several months, during which time normal biological processes may substantially reduce many contaminants and almost eliminate any turbidity. The use of bank-side reservoirs also allows water abstraction to be stopped for some time, when the river is unacceptably polluted or when flow conditions are very low due to drought. The London water supply system is one example of the use of bank-side storage: the water is taken from the River Thames and River Lee; several large Thames-side reservoirs such as Queen Mary Reservoir can be seen along the approach to London Heathrow Airport.

The East Branch Reservoir part of the New York City water
supply system, is formed by impounding the eastern tributary
of the Croton River

Cherokee Reservoir in Tennessee. It was formed after the impounding
of the Holston River Valley by the Tennessee Valley Authority in 1941
as a part of the New Deal's efforts to bring electricity to the Tennessee Valley.

Major Dams in India

Rain Water Harvesting

Rainwater Harvesting is a technique that is the process of saving and collecting rainwater using various means of various resources (such as agriculture etc.) for future use. Rainwater can be collected in natural reservoirs or artificial tanks. Storage of roof water is also a way of collecting rainwater.

It reduces soil erosion and flood hazards by collecting rainwater and reducing the flow of stormwater to prevent urban flooding. Most buildings that utilize rainwater harvesting systems have a built-in catchment area on top of the roof, which has a capacity of collecting large volumes of water in case of rainstorms

The different methods of rainwater harvesting include:
Rooftop rainwater harvesting – The rooftop becomes the catchments, and the rainwater from the building and houses are collected. The components of the rooftop rainwater harvesting are:
First, flush.
Transportation.
Catchment.
Filter.
Surface runoff harvesting – It is the system that collects rainwater, which flows away as surface runoff. The runoff rainwater is caught and used to recharge aquifers by adopting appropriate techniques.

Rainwater harvesting (RWH) is the collection and storage of rain, rather than allowing it to run off. Rainwater is collected from a roof-like surface and redirected to a tank, cistern, deep pit (well, shaft, or borehole), aquifer, or a reservoir with percolation, so that it seeps down and restores the ground water. Dew and fog can also be collected with nets or other tools. Rainwater harvesting differs from stormwater harvesting as the runoff is typically collected from roofs and other surfaces for storage and subsequent reuse.[2]: 10 Its uses include watering gardens, livestock,[3] irrigation, domestic use with proper treatment, and domestic heating. The harvested water can also be committed to longer-term storage or groundwater recharge.

Sewage Water Treatment Plants

Sewage treatment (or domestic wastewater treatment, municipal wastewater treatment) is a type of wastewater treatment which aims to remove contaminants from sewage to produce an effluent that is suitable to discharge to the surrounding environment or an intended reuse application, thereby preventing water pollution from raw sewage discharges.[2] Sewage contains wastewater from households and businesses and possibly pre-treated industrial wastewater. There are a high number of sewage treatment processes to choose from. These can range from decentralized systems (including on-site treatment systems) to large centralized systems involving a network of pipes and pump stations (called sewerage) which convey the sewage to a treatment plant. For cities that have a combined sewer, the sewers will also carry urban runoff (stormwater) to the sewage treatment plant. Sewage treatment often involves two main stages, called primary and secondary treatment, while advanced treatment also incorporates a tertiary treatment stage with polishing processes and nutrient removal. Secondary treatment can reduce organic matter (measured as biological oxygen demand) from sewage, using aerobic or anaerobic biological processes.