## 3 Results
### High-Frequency Physicochemical Characteristics of Inflow and Outflow  
#### 3.3.1 Flow Characteristics  
Outflow from the wetland following a rain event lasted an order of magnitude (or more) longer relative to outflow for the basin. For example, during a 3.7 cm rain event in September of 2018 that produced an estimated 1650 m\({}^{3}\) of runoff entering the basin, the outflow stage for the basin reached a peak of 152.9 cm and declined to 25.8 cm in 4.5 h (Figure 8). A similar-scale rain event (4.3 cm) producing 1911 m\({}^{3}\) or runoff entering the wetland occurred in September of 2019, and the outlet stage exceeded 103 cm and declined to 56 cm after 116 h. In November of 2018, a 1.1 cm rain event producing 486 m\({}^{3}\) of runoff resulted in a peak water stage at the outlet of the basin of 107 cm (Figure 9). The stage declined to 20 cm within 80 min. In November 2019, a 1.1 cm rain event producing 486 m\({}^{3}\) of runoff resulted in an outlet stage peak of 102 cm for the wetland, and the stage declined to 41.4 cm 90 h later. In December 2018, a 0.6 cm rain event producing 271 m\({}^{3}\) of runoff resulted in a peak stage near the basin outlet of 31.7 cm, and 4.67 h later the stage had lowered to 18.1 cm (Figure 10). During a 0.6 cm rain event in December 2019, runoff entering the basin was estimated to be 271 m\({}^{3}\) and the peak stage near the outlet of wetland was 67.8 cm. The stage declined from the maximum of 67.8 cm to 42 cm in just over 100 h. The differences in water level recession for the basin and wetland can be more easily quantified by reviewing the slopes of regression lines during each of the similar-sized storms. There was more than one order of magnitude difference in the slopes of regression lines for each event (Figures 8-10). The residence time of stormwater in the wetland was much greater in comparison to the basin. There were significant correlations between stage (cm) and outflow (L s\({}^{-1}\)) for the basin (\(p\) = 0.005) and wetland (\(p\) < 0.001). Therefore, as the stage increased and decreased in response to runoff, so too did the outflow. Overall, the mean storm size sampled for the dry basin and wetland were 1.6 cm and 1.3 cm of rain, respectively. The maximum storm size sampled was 4.3 cm for both, and the smallest rain event sampled for the basin (0.2 cm) and wetland (0.4 cm) were similar.  
Figure 7: Boxplots (**a**) and line plots (**b**) of flow weighted concentrations of dissolved organic carbon (DOC) at the inlet (I) and outlet (O) of the dry basin (B) and wetland (W). Statistical outliers represented by (*).  
Figure 8: Outlet stage response to a 3.7 cm rain event in September of 2018 for the dry detention basin (**a**,**b**). Outlet stage response to a 4.3 cm rain event for the wetland in September of 2019 (**c**,**d**). The slope of the stage decline for the basin (**b**) was 2 orders of magnitude steeper than the wetland (**d**). Grey-shaded boxes denote range of inset graphs (**b**,**d**).  
Figure 9: Outlet stage response to a 1.1 cm rain event in November of 2018 for the dry detention basin (**a**,**b**). Outlet stage response to a 1.1 cm rain event for the wetland in November of 2019 (**c**,**d**). The slope of the stage decline for the basin (**b**) was almost 2 orders of magnitude steeper than the wetland (**d**). Grey-shaded boxes denote range of inset graphs (**b**,**d**).