## 1 Introduction  
With the rapid development of urbanization, the increase of impervious areas has interrupted the water infiltration channel, which has greatly increased the rainfall runoff and peak discharge [1]. The heavy metals in urban stormwater runoff mainly come from automobile exhaust, industrial smoke and fossil fuel combustion, dust and various metal facilities. Heavy metals such as copper, zinc and lead are common components in stormwater runoff and usually with relatively high concentrations. Unlike organic pollutants, heavy metals are difficult to degrade in the environment and are easily accumulated in the human body through the food chain. Excessive intake of heavy metals in the human body may irritate the mucous membranes, leading to liver and kidney damage, capillary damage and central nervous system problems [2]. Cu(II) is essential for some biosyntheses in the human body, and micronutrients as animals and plants are well known, but it is toxic with high concentrations. When the concentration is above the threshold level, it can cause anemia and gastrointestinal discomfort. Infiltration facilities such as permeable pavements could remove pollutants in urban runoff to some extent. Typical pavement systems are mainly composed of materials such as sand and gravel. Because of the unique properties of these media, the adsorption capacity is very limited. The removal of heavy metals in runoff is mainly through the interception of pores in the media. However, with the operation of the permeable paving system, the problem of pore blockage, which is the bottleneck of the operation of the currently trapped system, also results in a significant reduction in the continuous retention of contaminants. In addition, with the long-term operation of the system, the extremely limited adsorption capacity was not able to achieve good removal efficiency for pollutants. Therefore, improving the adsorption capacity of the pavement system medium towards pollutants has a positive effect on reducing the water quality risks. In many countries, construction and demolition wastes are the main types of wastes in terms of weight. In Europe, more than 30% (_w/w_) of wastes generated is waste bricks. The production of brick-concrete construction wastes in China has been currently increasing year by year. The amount of this type of wastes accounts for 30% to 40% of the total amount of municipal waste. A large amount of construction wastes has piled up, which seriously pollutes the city's atmosphere, water and soil environment, and has a local impact on people's production and life. Recently, there has been an increasing interest in using construction wastes as adsorbents to remove pollutants from wastewater or stormwater. Construction waste bricks are used as the packaging media in percolation facilities. Using construction wastes in remediation were proposed as an alternative method to replace the current methods with a relatively high cost [3]. Due to many economic advantages, construction waste bricks are cheaper than other alternative adsorbents, such as activated carbon, natural and synthetic zeolites, and ion exchange resins. [PERSON] et al. showed that concrete blocks, crushed stone beds, and geotextiles in the permeable paving system can retain hydrocarbon contaminants and improve the quality of effluent [4]. [PERSON] et al. confirmed that using construction wastes as bioretention media can remove 90% of heavy metals in rainwater [1]. [PERSON] et al. showed that brick kiln chimney wastes could efficiently remove chromium from solutions and the removal capacity could reach 38.8 mg/g [5]. Although the results of using construction waste bricks to remove heavy metals are promising, there is still a need to better understand the removal efficiency and operational process such as how inlet concentration and residence time affect the removing of pollutants. [PERSON] et al. confirmed that a permeable paving system with plastic or stone can effectively remove heavy metals and the mechanism may be chemical sedimentation [6].