Perhaps the greatest value of an interconnected green space system is the financial benefit that may be gained when green infrastructure reduces the need for built infrastructure. Flood control and stormwater management in urban areas typically involve vast networks of underground storm sewers that feed into channelized streams or ditches and eventually into natural waterways. These systems are very expensive, and under extreme flood conditions they often fail.
Bellevue has reclaimed its natural systems through the coordinated design of a citywide park system and a stormwater management program. In the early 1970s the city government made a decision to change its stormwater systems from an underground piped system to a less expensive surface drainage system. Today two city agencies, the Storm and Surface Water Utility and the Parks and Recreation Department, use the same land to accomplish multiple objectives. The utility bears responsibility for water resources and has a budget for land acquisition.The parks department manages much of the utility's land for parks, ball fields, playgrounds, interpretive areas, and trails. Many of these open space assets are also elements of the stormwater system. As a result of this partnership, both agencies have reduced their costs while achieving their diverse objectives.
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