Water Cycle

Below is a broad description of the Coffs Harbour Water Cycle.  It explains the complex process of where water comes from, at what stage it's treated and how it's part of a never-ending cycle of precipitation and evaporation.

Evaporation

This is the process by which energy from the sun (solar energy) turns liquid water into water vapour. As the water molecules get hotter, they begin to move faster in the liquid. They collide more often with each other, and, gradually some water molecules move fast enough to break away from the others. They escape into the air - that is they have evaporated.  More than 80 per cent of the water vapour in the atmosphere is from water evaporated from the oceans. When this water evaporates the substances dissolved in it (like salt) remain behind.

Transpiration

Water is absorbed through the roots of plants and moves up through hollow tubes to the leaves. The movement of water up the plant is due to capillary action.
Leaves have small holes in them through which they can absorb carbon dioxide and release oxygen. Water vapour is also lost through evaporation from the pores of leaves. The process of water movement and loss from plants is called transpiration.

Precipitation

If water droplets in clouds join together to form drops between 2 and 6.5 mm in diameter, they may fall as rain. Fog or mist is really just low lying clouds. Hail forms when droplets of water freeze around a small core of ice. Hail stones increase in size by adding extra layers of ice as they are tossed up and down by rising and falling air currents common in thunderstorms. Dew is formed when water vapour condenses near the ground. On clear nights, the land will rapidly lose heat to the air. Any moist air near the surface will cool and condensation will occur. Frost forms when the surface temperature falls below freezing (0°C) resulting in ice crystals directly forming from the saturated air.

Run-off

Only some of the water soaks or infiltrates into the ground, a lot of it can run off either into rivers, lakes or into the ocean. Nearly 40% of all precipitation flows back across the land to seas and oceans.

Storage

Water is pumped from the river and stored in Karangi Dam for use in the urban areas.

Reticulation of Water Supply

Through a series of pumps, gravity pipes and reservoirs, water is supplied to domestic, commercial and industrial users throughout Coffs Harbour.

Waste Water collection

After use in the household or commercial organisations, waste water is collected and transported for treatment via a complex system of gravity mains and sewerage pumping stations.

Waste Water Treatment

Waste water is treated at one of 4 treatment plants located at various locations throughout the city.

Reuse of Treated Waste Water

Treated waste water is used in treatment plants for washing down. It is also used on a number of sporting fields, golf courses and other commercial enterprises.

Ocean Release

Waste water that is not reused is then released to the ocean via an ocean outfall.