{"id":3747,"date":"2018-04-25t11:20:21","date_gmt":"2018-04-25t16:20:21","guid":{"rendered":"https:\/\/snyder-associates.u5fz9z3h-liquidwebsites.com\/?post_type=snyder-projects&p=3747"},"modified":"2023-07-10t14:28:48","modified_gmt":"2023-07-10t19:28:48","slug":"hamilton-drain-flood-control-improvements","status":"publish","type":"snyder-projects","link":"\/\/www.dicovercards.com\/projects\/hamilton-drain-flood-control-improvements\/","title":{"rendered":"hamilton drain watershed flood control improvements"},"content":{"rendered":"

development leads to increased flooding concerns<\/strong><\/span><\/h2>\n

for many decades, increasing commercial development<\/a> and urbanization in northeast des moines and central polk county led to recurring and frequent flooding within the hamilton drain watershed. by their nature, industrial<\/a> and commercial land uses involve large areas of impervious structures that prevent stormwater infiltration, such as parking lots and buildings. the combination of increased runoff volume and decreased runoff time results in significantly higher flow rates into the conveyance system that receives the storm runoff.<\/p>\n

another factor leading to the area\u2019s stormwater issues is the flat topography. with few areas to store and detain higher flows, high amounts of stormwater easily overwhelmed the system\u2019s capacity, causing rivers, lakes, and streams to overflow. residents in the area frequently reported overflows occurring even during relatively minor storm events. these floods often caused damage to residential and commercial properties, as well as roadways<\/a> and other 世界杯足球比赛预选赛 infrastructure.<\/p>\n

to better understand the problem and determine potential solutions, polk county commissioned several stormwater studies in the mid-1980s. recommendations from the findings included the construction of numerous storm sewer and channel improvements, along with the construction of 11 regional stormwater detention basins. since the completion of these initial studies, six detention basins and many storm sewer conveyance upgrades were constructed. these improvements eased flooding across portions of the watershed, but did not entirely eliminate the problem.<\/p>\n

documenting flood damages guides mitigation efforts<\/strong><\/span><\/h2>\n

to further mitigate flooding in the area, snyder & associates began assisting polk county on a federal emergency management agency (fema) hazard mitigation grant program (hmgp)<\/a> project in 2009. to determine viable damage for mitigation, polk county provided our team with documented flood damage data dating back to 1998. after analysis, the damages were defined as economic losses associated with road closures during flood events. this designation resulted in six specific areas being targeted for flood mitigation within the hamilton drain watershed based on recurring flood events. these areas included:<\/p>\n