A particular water regime will favour certain species. It will therefore affect the composition of the community developing from seeds and eggs in the soil.

Continuous flooding and drying creates habitats that are similar over large areas for long periods. When water levels fluctuate, habitats change in conjunction with the water levels. The variety of habitats then created within the wetland encourages diversity amongst the biota.

Rapid flooding and drying induced by pumping water into or out of a wetland is often stressful for plant establishment and growth. Allowing water levels to fluctuate naturally favours the biological diversity of a wetland.

(Taken from: Brock, M.A., Casanova, M.T., Berridge, S.M., (2000). Does your wetland flood and dry? Water regime and wetland plants. LWRRDC, UNE, DLWC and EA.)

Wetlands are one of the most biologically diverse and productive ecosystems on earth. They occur on almost all continents (except Antarctica), in all climatic zones, on the coast, inland, and can be formed naturally or man-made. They provide food, fibre and medicines, a buffer from storms and floods, and act as water filters. They provide windows into the past, habitat for a wide range of plants and animals, a place of beauty and tranquillity. Wetlands are also one of the most threatened natural systems in the world.

As dams are often the most significant and direct modifiers of natural river flows, the decommissioning of Lake Mokoan, is a key step towards returning a more natural water regime to the Broken System.

Water regime is the term used to describe the pattern of water presence and absence in a wetland. Wetlands include standing water such as ponds, puddles and dams, as well as flowing water - creeks, streams and rivers.

There were in excess of 300 separate assets built to operate and manage Lake Mokoan as a storage facility. These assets have been identified and assessed to determine whether they should be retained, removed or rendered inoperable. The assessment process involves identifying risks of implementing any one option, compared with the current situation. Risks to the community, environment, and the future management of the land in question on a wide range of issues e.g. safety, flooding, public liability will be considered.

Major infrastructure components that are under investigation are outlined in the following table.

Main Project Features Components Inlet Works -------------> - Inlet Channel     - Broken River Diversion Works     - Blind and Kennedy's Creek Crossing     - Holland Creek Diversion Works     - Channel Drainage Works     - Bridges     - Measuring (Drop) Structures Dam Structure ----------> - Embankment Outlet Works ------------> - Intake Tower     - Outlet Culvert     - Outlet Channel     - Channel Drainage Works     - Bridges     - Measuring (Drop) Structures

Further hydraulic studies to understand drainage patterns and requirements along each of the inlet and outlet channel alignments and catchment areas.

Consultation - this process will require consultants to visit each of the landowners adjacent to the inlet and outlet channels and the embankment to identify any issues which need to be taken into account in order to formalise a final draft Asset Decommissioning Package. This process will also include discussions with council and other road, rail, communications, power and emergency service agencies.

	Recommendations for the embankment opening and the outlet structures,
	Preliminary plans for embankment opening, concrete removal and the removal and protection of other structures,
	Identification of any significant safety issues and actions to address,
	Identification of any socio-economic implications,
	An estimation for the above works and an implementation program for the timing of the above works.

The actual works associated with the decommissioning of assets will not commence until after harvesting of water ceases in 2008/09