The research presented here addressed two aspects of stormwater prevention. The first aspect was the elimination of stormwater through retention basins. Infiltration rates were measured by Double Ring Infiltrometer (DRI) within 40 basins in Alachua, Leon, and Marion counties. Measured rates were compared to designed rates to determine whether basins were operating as designed. The 40 basins were equally divided between residential and Florida Department of Transportation land uses. Texture analysis was also performed on soil samples taken from each infiltration location; soil types ranged from sand to sandy clays. Eleven of the 40 basins were also instrumented with monitoring equipment to measure drawdown rates. Three basins did not adequately store water to determine drawdown rates. However, 6 of the remaining 8 basins had drawdown rates less than DRI rates while the other 2 basins were not statistically different from DRI rates. This indicated that subsurface conditions were controlling basin drawdown rates. DRI rates frequently varied by at least an order of magnitude within basins. Based on DRI rates, 16 (40%) basins had rates less than their designed rates, 10 (25%) had rates equal to their designed rates, and 14 (35%) basins had rates greater than their designed rates. Additionally, FDOT basins had a higher proportion of basins with greater DRI rates than residential basins and coarser basins were also more likely to have DRI rates greater than designs. Greater size and diversity of vegetation resulting from less frequent maintenance in FDOT basins may have resulted in a higher proportion of sites with rates equal to or greater than designs.;The second aspect is stormwater generation. Traffic during construction has been shown to compact soils, resulting in reduced porosity and infiltration rates and increased runoff. In agricultural settings soil amendments have been found to counteract compaction effects. Two soil amendments (compost and fly ash) were evaluated for mitigating compacted soils. Forty-two lysimeters were filled with two soils (Orangeburg Sandy Loam and Arredondo Fine Sand) overlaying a drainage layer of quartz stone. Runoff was directed into collection tanks and volumes were recorded. The soils were compacted to levels representative of observed levels found in North Central Florida based on bulk densities and infiltration rates. Runoff and leachate samples were analyzed for nitrogen species and orthophosphorus. Incorporating fly ash did not significantly reduce runoff. Tillage to at least 10 cm decreased runoff compared to compacted soils. However, adding compost treatments did not significantly reduced runoff compared to just tillage.
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机译：这里介绍的研究涉及防洪方面的两个方面。第一个方面是通过保留盆地消除雨水。用双环渗透仪（DRI）测量了阿拉卡瓦，莱昂和马里恩县40个盆地中的入渗率。将测得的流量与设计流量进行比较，以确定流域是否按设计运行。这40个盆地在住宅用地和佛罗里达交通运输部土地用途之间平均分配。还对从每个入渗点采集的土壤样品进行了质地分析。土壤类型从沙子到沙质粘土不等。 40个盆地中有11个还配备了监测设备，以测量水位下降速度。三个流域没有足够的储水量来确定水位下降率。但是，其余8个盆地中的6个盆地的降水率低于DRI率，而其他2个盆地与DRI率在统计学上没有差异。这表明地下条件正在控制盆地的降水速度。流域内DRI率经常变化至少一个数量级。根据DRI比率，有16个（40％）盆地的水价低于其设计水价，有10个（25％）的水价等于其设计水价，有14个（35％）的水盆其水价高于其设计水价。此外，FDOT盆地的DRI率要高于住宅盆地，而较粗糙的盆地的DRI率也比设计更大。由于FDOT盆地维护较少而导致的植被面积更大，种类繁多，可能导致比例等于或大于设计值的地点比例更高。第二个方面是雨水的产生。事实表明，施工期间的交通运输会压实土壤，导致孔隙率和渗透率降低，径流增加。在农业环境中，已发现土壤改良剂可抵消压实效果。评价了两种土壤改良剂（堆肥和粉煤灰），以减轻压实土壤。 42个测渗仪充满了两种土壤（Orangeburg Sandy Loam和Arredondo Fine Sand），覆盖了石英石的排水层。径流直接进入收集池并记录体积。根据堆密度和入渗率，将土壤压实至代表在佛罗里达州中北部发现的水平。分析了径流和渗滤液样品中的氮和正磷。掺入粉煤灰并不能显着减少径流。与压实土壤相比，耕种至至少10 cm时径流减少。但是，与单纯的耕作相比，添加堆肥处理并没有显着减少径流。
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