Water covers about 71 % of the Earth's surface. However, only 1% of it is available for safe use (available freshwater). Roughly 10 percent of the world's annual water runoff is withdrawn for human use each year.

In the Philippines, its primary water sources are rivers, lakes, river basins, and groundwater reservoirs. Approximately 28.52 billion m3 of water was withdrawn from the said sources: 74% (21.10 billion m3) was used for agricultural purposes, 9% (2.57 billion m3) for industrial processes, and 17% (4.85 billion m3) for domestic consumption.

Because of growing freshwater demand from different industries, there has been an observed increase in treated wastewater worldwide. This led the competition for freshwater to intensify among industrial, municipal, and agricultural sectors. In the Philippines, inadequate water supply forces in Metro Manila forces residents to rely on drinking water resources that are considered unsafe. Limited water supply urges people to store more water, which provides more opportunities for mosquitoes to breed, resulting in high dengue fever cases in the country.

To combat issues concerning intermittent water supply, strategies such as improved rainwater collection systems and desalination technologies are adapted by local governments to ensure that water used for domestic purpose is safe, safeguarding one's health.

Two critical systems that are important in diminishing the spread of waterborne diseases include water collection, treatment, and distribution to provide safe drinking water to the community and wastewater collection and treatment that removes contaminants before being transported back to local reservoirs.

Urban water systems get their water from a local stream, reservoir, or groundwater system. Larger cities tend to rely heavily on surface water supplies, whereas small community water systems take advantage of groundwater more often. The water that is collected goes through the cleaning and treatment process.

The purpose of water treatment systems is to bring raw water up to drinking water quality. The particular type of treatment equipment required to meet these standards depends mainly on the source of water.

Potable water, also called drinking water, is used primarily for drinking, showering, hand washing, cooking, and other sanitary needs. Also, it is filtered and treated correctly and is finally free from all the contaminants and harmful bacteria.

Freshwater, on the other hand, is found in lakes, rivers, ponds, wetlands, and streams, and it does not contain a large amount of salt, unlike saltwater. Plants, animals, including humans, heavily rely on freshwater for daily survival.

Greywater, also known as sullage, refers to the wastewater generated in households or office buildings from streams without fecal contamination. It does not include the discharge of toilets or fecally contaminated wastewater.

The term "Blackwater" describes wastewater containing feces, urine, and flushwater from water closets. It contains pathogens that must be decomposed before they can be released safely into the environment.

Stormwater usually flows from rooftops, over paved areas, bare soil, and sloped lawns. The runoff also collects and transports animal waste, litter, salt, pesticides, fertilizers, oil & grease, and other pollutants that are considered harmful as it reaches creeks.

Based on what I’ve learned on studying stormwater and water conservation, I have found ways on how to reduce stormwater as a college student. These include clearing away leaves and debris and avoiding dumping any trash in storm drains. Also, planting rain gardens will be highly significant in reducing stormwater, for it absorbs stormwater runoff. Cleaning and proper disposal of waste will also prevent harmful bacteria from washing towards local waterways.

Water harvesting encompasses various methods of conserving and collecting water from runoff. The most popular methods are rainwater harvesting and recharging of the groundwater table. Rainwater harvesting involves collecting the rainwater directly or recharging it to the ground using a recharging pit to increase groundwater storage. On the other hand, recharging groundwater is a modern version of water harvesting wherein pits, and deep wells are being constructed primarily to collect water which then feeds and raises the groundwater level.

Converting sewage sludge into renewable energy is viably becoming a trend as it can be used for wastewater treatment and can potentially supply electrical grids. The conversion of sewage to energy is made possible by separating the liquid and solid waste. Solid waste can be mixed with food waste in order to produce biogas which is used for cooking and also has the potential to provide electricity. On the other hand, liquid waste is used to grow microalgae that produce biodiesel.

Biogas is an environmentally-friendly energy source for it consumes methane gas instead of releasing it into the atmosphere. Thus, this reduces the human dependency on fossil fuel to meet energy demands.