在不降雨时，雨水排口理论上应该没有水流出。然而，由于雨污管网错接、混接问题普遍存在，雨污分流不彻底，在不降雨时和降雨时，都会有污水从雨水排口流出。即便前期完成了雨污管网的分流改造，南方地区也会由于地面沉降导致雨污水管道破碎，污水会通过破损的管道流入雨水排口。此外，南方地区降雨频繁，大量的初期雨水会通过雨水排口进入河流。未经任何处理的污染物通过雨水排口进入河流，是导致南方地区河湖水质超标的重要原因。对雨水排口的污染物进行有效管控，成为亟待解决的问题。

目前通常采用截流井对雨水排口的污染物进行间接的管控。这种方式既不能解决不降雨时雨水口排污的问题，也不能根据雨水的水质和水量特征实时调整运行工况，因此无法对雨水排口的污染物进行有效地管控。雨水智能排口是在雨水排口出水处设置的雨污水收集和输运装置。该装置具有水位和水质传感器，可以根据排口内污水的水量和水质变化，动态地将高污染的水输送到周边的污水管网，将低污染的水排入河湖，从而减少雨水排口的排污量。

本研究以提高雨水智能排口的污染截流量并降低运行能耗为目标，以回答何时调水、怎么调水、调多少水三个关键问题为导向，设置水质水量分析、调度规则构建、硬件参数设计、调度参数优化四方面内容（水质水量分析回答何时调水的问题，调度规则构建和硬件参数设计回答怎么调水的问题，调度参数优化回答调多少水的问题），对智能排口的设计和运行参数进行优化，提高雨水智能排口的综合效益。主要研究成果包括：

（1）雨水智能排口水量水质特征分析

雨水智能排口水体中的TDS与氨氮、COD、总磷等水质指标之间存在着显著的正相关关系。在不同的降雨情况下，排口内部水体TDS含量和液位的变化趋势存在显著差异。大雨和中雨期间，随着液位上升TDS含量呈现下降趋势。小雨时期，降雨发生前，排口液位保持稳定状态，而TDS含量会缓慢上升；降雨初期TDS的变化趋势与大雨和中雨过程相似，在雨水的稀释作用下，TDS浓度因液位上升而下降。在非降雨时期，TDS与液位之间无明显关联。同时，不同时期的TDS浓度也存在区别。非降雨时期TDS浓度较高，中雨时期TDS浓度最低，而在大雨时期，TDS浓度迅速降低后又升高。

在不同的降雨情况下，雨水智能排口的入流量和液位的变化趋势基本相似，排口的入流量和液位几乎同时变化。排口开始排水后，随着雨势逐渐减小，排口内部液位缓慢降低，最终达到动态平衡。研究发现，在大雨和中雨期间不同排口对雨量的响应速度有明显的差异，这种差异性揭示了雨水智能排口在设计和运行中面临的挑战。水量较大时，排水系统需要时间来适应降雨模式的变化，气候变化可能导致降雨模式变得更加不可预测，超出了系统的设计处理能力，导致排口不能很好地应对极端天气带来的影响。

（2）雨水智能排口优化调度规则构建

建立雨水智能排口调度规则，提出了智能排口调度系统关键参数的优化设置，包括启动低水位(H0)、关泵高水位(H1)、警戒水位(Hw)以及水质监测参数等。新的调度规则为：当排口井内水位高于H0低于H1且污水水质差于当地污水排放标准时，污水泵开始工作，泵出污水；当排口井内水位高于H0低于H1且污水水质优于当地污水排放标准时，污水泵不工作；当排口井内水位高于H1且污水水质优于当地污水排放标准时，污水泵停止工作；当排口井内水位高于H1且污水水质差于当地污水排放标准时，污水泵继续工作，防止污水溢流；当排口井内水位低于警戒水位Hw时，污水泵停止工作，防止设备干转。

雨水智能排口硬件参数设计

针对雨水智能排口硬件参数中的挡板高度(H2)进行优化设计。研究结果表明，挡板高度的改变对溢流和TDS排放量有显著影响，表现为先下降后上升的趋势。当调整挡板高度时，随着挡板高度H2的增加，控制溢流量的因素由启泵低水位逐渐转向关泵高水位。即在较低的挡板高度H2下，控制启泵低水位较为有效，而在较高的H2下，控制关泵高水位比较有效。

雨水智能排口调度参数优化

针对雨水智能排口运行参数，包括启动低水位(H0)、关泵高水位(H1)、警戒水位(Hw)以及水质监测参数等进行优化。对雨水智能排口，保持出水挡板高度H2不变时，启泵低水位的值越低，溢流量及总TDS排放量越小；在该情景下，保持启泵低水位在0.1–0.33 m时可以使得雨水排口的溢流量及总TDS量最小。关泵高水位的值越高，溢流量及总TDS排放量越小；在该情景下，保持关泵高水位值高于挡板高度值，即高于0.54 m时可以使得雨水排口溢出的水量及总TDS量越少。在高水量下，启泵低水位不再是雨污水溢流的主要控制因素，关泵高水位是雨污水溢流的主要控制因素。针对雨水智能排口的能耗优化，从启泵低水位的角度来看，选择一个相对较高的启泵低水位有助于减少泵的耗电量；在该情景下，保持启泵低水位高于0.5 m，可以降低排水系统的耗电量。而在关泵高水位的考量上，需要在结合挡板高度的情况下选择合适的关泵高水位参数。在该情景下，关泵高水位低于0.54 m（挡板高度）时，可以降低设备运行的耗电量。

In the absence of rainfall, stormwater outlets theoretically should not discharge any water. However, due to common misconnections and cross-connections in rain and wastewater networks, improper separation of stormwater and wastewater occurs, leading to sewage discharge from stormwater outlets both during dry weather and rainfall events. Even after the completion of stormwater and wastewater network separation improvements, subsidence in southern regions can result in cracked stormwater pipes, allowing sewage to enter stormwater outlets through damaged pipes. Additionally, frequent rainfall in southern regions causes a large volume of initial rainwater to flow into rivers through stormwater outlets. The untreated pollutants entering rivers through stormwater outlets are a significant contributor to water quality exceedances in rivers and lakes in southern regions. Effective control of pollutants from stormwater outlets is an urgent issue that needs to be addressed.

Currently, the common practice involves using detention tanks to indirectly control pollutants from stormwater outlets. However, this method does not address the issue of pollution discharge from stormwater outlets during dry weather or allow real-time adjustment of operating conditions based on the quality and quantity of stormwater, leading to ineffective control of pollutants from stormwater outlets. Intelligent stormwater outlets are designed at the outlet points to collect and transport stormwater and sewage. Equipped with water level and water quality sensors, these devices dynamically convey highly contaminated water to the surrounding sewer network based on changes in water quantity and quality within the outlet, while diverting low-contaminant water to rivers and lakes, thereby reducing pollution discharged from stormwater outlets.

This study aims to enhance the pollution interception capacity of intelligent stormwater outlets and reduce operational energy consumption. Addressing the key questions of when to adjust water flow, how to adjust water flow, and how much water to adjust, the study focuses on water quality and quantity analysis, scheduling rule development, hardware parameter design, and scheduling parameter optimization. By optimizing the design and operational parameters of intelligent stormwater outlets, the study aims to improve the overall efficiency of these systems. Key research outcomes include:

(1) Analysis of water quality characteristics of intelligent rainwater outlet

There is a significant positive correlation between Total Dissolved Solids (TDS) in the water of intelligent stormwater outlets and water quality indicators such as ammonia nitrogen, Chemical Oxygen Demand (COD), and total phosphorus. Under different rainfall conditions, there are significant differences in the variations of TDS content and liquid level within the outlet. During heavy and moderate rainfall, TDS content decreases as the liquid level rises. In light rain periods, before rainfall, the outlet liquid level remains stable while TDS content slowly increases; during the initial rainfall, the trend of TDS changes is similar to that of heavy and moderate rain, with TDS concentration decreasing due to the dilution effect of rainwater as the liquid level rises. In non-rainfall periods, there is no obvious correlation between TDS and liquid level. Additionally, there are differences in TDS concentrations at different times. TDS concentration is higher in non-rainfall periods, lowest during moderate rainfall, and rapidly decreases and then increases again during heavy rainfall.

Under different rainfall conditions, the inflow and liquid level variations of intelligent stormwater outlets are similar, with the inflow and liquid level changing almost simultaneously. Once the outlet begins to discharge water, the internal liquid level gradually decreases as the rainfall intensity decreases, ultimately reaching a dynamic balance. The study found that different outlets respond to rainfall at different speeds during heavy and moderate rainfall, highlighting the challenges faced in the design and operation of intelligent stormwater outlets. When the water volume is high, the drainage system needs time to adapt to changes in rainfall patterns, and climate change may lead to more unpredictable rainfall patterns, exceeding the system’s designed handling capacity and resulting in the outlet not effectively coping with the impacts of extreme weather.

(2) Construction of intelligent rainwater outlet optimization scheduling rules

In this study, scheduling rules for intelligent stormwater outlets were proposed, along with the optimization of key parameters for the scheduling system, including the activation low water level (H0), pump shutdown high water level (H1), warning water level (Hw), and water quality monitoring parameters. The new scheduling rules are as follows: when the water level in the outlet well is above H0 but below H1, and the wastewater quality is worse than the local wastewater discharge standard, the wastewater pump starts working to pump out the wastewater; when the water level is above H0 but below H1 with wastewater quality better than the local discharge standard, the pump remains idle; when the water level is above H1 with wastewater quality better than the local discharge standard, the pump stops working; when the water level is above H1 with wastewater quality worse than the local discharge standard, the pump continues to work to prevent wastewater overflow; and when the water level is below the warning level Hw, the pump stops working to prevent dry operation of the equipment. 

(3) Hardware parameter design of intelligent rainwater outlet

Optimization design was conducted on the baffle height (H2) of intelligent stormwater outlet hardware parameters. The study results showed that changes in baffle height have a significant impact on overflow and TDS discharge, exhibiting a trend of initially decreasing and then increasing. When adjusting the baffle height, as H2 increases, the factor controlling overflow switches from the activation low water level to the pump shutdown high water level. In other words, a lower baffle height (H2) effectively controls the activation low water level, while a higher H2 effectively controls the pump shutdown high water level. 

(4) Optimization of intelligent rainwater outlet scheduling parameters

Optimization was also conducted for operational parameters of intelligent stormwater outlets, including H0, H1, Hw, and water quality monitoring parameters. For a constant outflow baffle height (H2), a lower activation low water level results in smaller overflow and total TDS discharge; maintaining the activation low water level between 0.1-0.33 m minimizes overflow and total TDS discharge. A higher pump shutdown high water level results in smaller overflow and total TDS discharge; maintaining the pump shutdown high water level above the baffle height, i.e., above 0.54 m, reduces overflow and total TDS discharge from the stormwater outlet. In high water situations, the pump shutdown high water level becomes the primary control factor for stormwater overflow instead of the activation low water level. Regarding energy consumption optimization of intelligent stormwater outlets, selecting a relatively higher activation low water level reduces pump power consumption; maintaining the activation low water level above 0.5 m decreases the energy consumption of the drainage system. When considering the pump shutdown high water level, selecting an appropriate parameter in conjunction with the baffle height can reduce equipment operating energy consumption; setting the pump shutdown high water level below 0.54 m (baffle height) decreases energy consumption.