Retention Ponds Retention ponds have become increasingly common in jurisdictions requiring that storm water be contained and made use of on-site, as opposed to being directed off-site via a storm water system. The ponds are designed to maintain a certain level of water, as shown in Figures 14.25-A and 14.25-B. Additional water-holding capacity is provided based on assumed storm water events. The canal-like basin shown in Figures 14.25-A was designed to allow the upper area of the basin to serve some purpose such as passive, or in some cases active, recreation uses. The upper slopes (14.25-B) are planted to hold the soil and to serve as a surface for passive uses such as picnicking or field sports. In the case of Figures 14.25-A, the upper slopes provide wildlife habitat and serve nature study purposes, while the area in Figures 14.25-B provides for valuable park and recreation uses, serving adjacent residential neighborhoods.
Figure 14.25-A Retention pond with upper slopes supporting native plants in a residential neighborhood in Voorhof, the Netherlands
Figure 14.25-B Retention canal located in a more dense residential neighborhood in Voorhof, the Netherlands
The example in Figure 14.26 of a retention basin and surrounding grassy slopes was designed to serve a diverse range of active and passive park uses for surrounding neighborhoods. A sandy beach was
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Landscape Site Grading Principles
