San Dieguito River Park
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Wetlands are nature’s water filtration system. They are made up of low meadow, high marsh, shallow marshlands and open water. As the river flows in, and rains wash stormwater through a wetland area, the roots of many wetland plants and microbes act to filter and absorb pollutants. They also slow the waters velocity so that heavy metal toxins can settle into the sediment layers rather than be carried to the ocean. In a big storm event, or when a flood creates high water, a wetland provides area for water to spread out and slow down before it erodes adjacent lands or invades properties at higher ground. Slowing the river flow also replenishes the marshlands and beaches with new sand transport from inland areas. The natural processes of tidal action and river flows meet in a coastal lagoon here at San Dieguito River Park . These restored natural lagoon cycles make the water cleaner for people at the beach, and help keep pollutants out of the food chain we share with fish and animals. Wetlands contribute to a healthy system.