Xing Fang

Auburn University | AU · Department of Civil Engineering

Construction sites rely on erosion control practices to protect bare slopes and prevent soil loss. The effectiveness of certain erosion controls is often under-evaluated if they are not a part of a product evaluation program. Furthermore, erosion controls in general are not fully understood regarding how their performance can be affected by site sp...

Human safety is paramount in flood disasters. Current research indicates that the majority of fatalities in such disasters are due to people moving in water. Existing studies on human stability in floods have primarily focused on the static resistance of a standing posture against water flow, neglecting the realistic scenario where people need to m...

Understanding and modeling water quality in a lake/reservoir is important to the effective management of aquatic ecosystems. The advantages and disadvantages of different water quality models make it challenging to choose the most suitable model; however, direct comparison of 1-D and 3-D models for lake water quality modeling can reveal their relat...

The widespread application of permeable pavements in urban stormwater management practices requires a quick and easy model to evaluate their hydrological function during different clogging stages. The Natural Resources Conservation Service-Curve Number (NRCS-CN) method has extensively used for predicting direct runoff from rainfall. However, the st...

Implementing proper methods and techniques for construction stormwater management brings numerous benefits in protecting the environment, maintaining social justice, and enhancing sustainability within the construction industry. Flocculants improve construction stormwater management on active job sites by enhancing the function of temporary sedimen...

Study Region: China Study Focus: In sponge city construction in China, rainfall data is the key to determining the rainwater source control scale. However, changes in rainfall characteristics can reduce the representativeness of the data. To obtain stable volume capture ratios (VCRs) of the annual rainfall through as little rainfall data as possibl...

The effect of varying initial soil moisture (θin) of a given soil on the drawdown curve measured using the Modified Philip-Dunne Infiltrometer (MPDI) and consequently on the estimated saturated hydraulic conductivity (Κs) value, was investigated. The laboratory tests completed using three different types of soil show that the drawdown curve was sen...

Flocculants provide an innovative solution for managing construction stormwater runoff with their efficiency in reducing turbidity in the effluent. With proper application and dosage, these chemicals improve the performance of sediment control practices in capturing fine-sized soil particles. Flocculants function by providing electromagnetic charge...

Sediment remains one of the most commonly occurring pollutants affecting the U.S.’s water bodies, as identified by the United States Environmental Protection Agency (USEPA) ( 1). Construction activities largely accelerate soil erosion and subsequent sediment deposition. The National Pollutant Discharge Elimination System Construction General Permit...

The permeable brick pavement system (PBPs) is one of a widely used low impact development (LID) measures to alleviate runoff volume and pollution caused by urbanization. The performance of PBPs on decreasing runoff volume is decided by its permeability, and it was general described by hydraulic conductivity based on Darcy's law. But there is large...

Due to eutrophication, many lakes require periodic management and restoration, which becomes unpredictable due to internal nutrient loading. To provide better lake management and restoration strategies, a deterministic, one-dimensional water quality model MINLAKE2020 was modified from daily MINLAKE2012 by incorporating chlorophyll-a, nutrients, and...

In shallow lakes, water quality is mostly affected by weather conditions and some ecological processes which vary throughout the day. To understand and model diurnal‐nocturnal variations, a deterministic, one‐dimensional hourly lake water quality model MINLAKE2018 was modified from daily MINLAKE2012, and applied to five shallow lakes in Minnesota t...

The FullSWOF-ZG (Full Shallow Water Overland Flow with infiltration determined by Zones and Grate-inlet submodules) program was used to simulate the road-bioretention (RB) stripe and evaluate the performance of the RB stripe with three types of curb inlet. The program was revised from the open-source FullSWOF-2D program and the validation results i...

Climate change and eutrophication are potential environmental stressors that are altering water quality conditions and then influence indigenous fish habitat in glacial lakes across the Midwest states. Several approaches were used to study the effects of climate changes with or without eutrophication on fish habitat, which was quantified using a si...

The characteristics of colloids in urban road runoff with different traffic in Beijing, China, such as concentration, particle size, chemical property, and affinity for heavy metals were determined. The concentration of colloids was high, and an evident first flush effect was found in the runoff of road with heavy traffic. A large portion of colloi...

A distributed-framework hydrologic modeling system (DF-HMS) is a primary and significant component of a distributed-framework basin modeling system (DFBMS), which simulates the hydrological processes and responses after rainfall at the basin scale, especially for non-homogenous basins. The DFBMS consists of 11 hydrological feature units (HFUs) invo...

To better simulate the river basin hydrological cycle and to solve practical engineering application issues, this paper describes the distributed-framework basin modeling system (DFBMS), which concatenate a professional hydrological model system, a geographical integrated system, and a database management system. DFBMS has two cores, which are the...

A distributed-framework basin modeling system (DFBMS) was developed to simulate the runoff generation and movement on a basin scale. This study is part of a series of papers on DFBMS that focuses on the hydraulic calculation methods in runoff concentration on underlying surfaces and flow movement in river networks and lakes. This paper introduces t...

This paper presents the application of a distributed-framework basin modeling system (DFBMS) in Taihu Basin, China. The concepts of professional modeling systems and system integration/coupling have been summarized in the first three series papers. This study builds a hydrologic and hydrodynamic model for Taihu Basin, which is in the lowland plain...

A granular sludge-clay (GSC) adsorbent was prepared based on the sludge obtained from drinking water purification plant and clay, with a mass ratio of 1:2. The adsorption of Cd(II), Cu(II), and Zn(II) onto GSC was also investigated. The adsorption process was highly pH-dependent, with the maximum adsorption of Cd(II), Cu(II), and Zn(II) occurring a...

Making a deep cut on the curb inlet has been used in some sponge-city (SPC) projects for road-bioretention stripes to manage stormwater runoff since they were easily implemented in the field. The efficiencies of the deep-cut curb inlets in those projects were unknown for lacking equation to evaluate their efficiencies. Two kinds of retrofit scenari...

Green roofs can retain urban rainfall runoff, but there are doubts about whether they can reduce urban nonpoint source pollution. To explore the factors affecting the ability of green roofs to reduce nutrients in rainfall runoff, nine types of extensive green roofs (EGRs) were analysed during 38 natural rainfall events and two early spring irrigati...

Discharge of sediment-laden stormwater from active construction sites, such as highway construction projects, continues to be a growing concern in the construction industry. Therefore, there has been an increased interest in research efforts to test many different erosion and sediment control practices. The purpose of this research effort was to te...

Construction site erosion and resulting sedimentation constitutes one of the greatest non-point source pollution threats to our nation’s waterways. Erosion control practices are important aspects of any construction project due to their ability to limit the process of erosion. Testing erosion control practices under simulated rainfall representativ...

Abstract Thermal stratification in reservoirs is a critical process that regulates downstream riverine energy and biogeochemical cycling. Current stratification models either simplify vertical energy process, reservoir geometry or neglecting the effects of reservoir operation. Here we present a new multilayer reservoir stratification model that can...

This study aims at furthering our understanding of the Modified Philip–Dunne Infiltrometer (MPDI), which is used to determine the saturated hydraulic conductivity Κs and the Green–Ampt suction head Ψ at the wetting front. We have developed a forward-modeling algorithm that can be used to simulate water level changes inside the infiltrometer with ti...

The rainwater source control (RSC) is an important part of modern urban stormwater management. To quantitatively evaluate the role of source control in the overall urban drainage system, rainfall depths of different return periods and rainfall durations were calculated based on the rainfall intensity formulas of 342 cities in China and used to desi...

Green roof is an important measure in “Sponge Cities” to reduce the runoff and improve the runoff quality. The runoff quantity and quality control capacity of five types of extensive green roofs (EGRs) were analyzed in Beijing for 51 nature rainfall events and 6 simulated events from July 2017 to October 2018. Different module scales (sizes) and su...

Much more attention and focus should be paid on studying the curb inlet interception efficiency and its design because curb inlet is an important component for road-bioretention facilities. It allows the runoff from the road surface to get into bioretention and influences the performance of the road-bioretention strip directly. Most of the currentl...

This study focused on the effects of external conditions on the performance of grass swales installed to improve stormwater runoff quality. Four grass swales in Beijing and Shenzhen with different underlying surface characteristics, antecedent dry weather period (ADWP), transport within the grass swales, and rainfall characteristics, were compared...

An updated two-dimensional flow simulation program, FullSWOF-ZG, which fully (Full) solves shallow water (SW) equations for overland flow (OF) and includes submodules modeling infiltration by zones (Z) and flow interception by grate-inlet (G), was tested with 20 locally depressed curb inlets to validate the inlet efficiency (Eci), and with 80 undep...

Sediment basins are temporary practices commonly used to detain stormwater runoff and capture suspended sediment on construction sites. A 79.0 m 3 (2790 ft 3) sediment basin testing apparatus at the Auburn University-Erosion and Sediment Control Testing Facility was used to provide a series of controlled and repeatable, large-scale tests to underst...

The objective of this study was to investigate the flow dynamics and temperature characteristics under different reservoir operation scenarios and weather conditions in the river-reservoir system, which can be used to set scientific guidelines for river management and conservation planning strategies. The calibrated three-dimensional model provided...

The two-dimensional overland flow simulation program, FullSWOF_2D, was revised to include submodules of determining infiltration by zones (Z) and grate-inlet (G) drainage from a 2D surface to a 1D pipe flow. The updated program, FullSWOF-ZG, was used to evaluate the performance of a road-bioretention strip (RBS) system and explore/understand key pa...

We quantified effects of future climate warming on temperature and stability in a variably stratified, hypereutrophic reservoir with large fluctuations in water level by calibrating a 2-D model (CE-QUAL-W2, version 3.7.1, Portland State University, Portland, USA) of reservoir hydrodynamics using a time series (1992 to 2011) of inflow and air and wa...

The runoff retention effectiveness of 10 extensive green roof (EGR) modules (100 mm substrate planted Sedum lineare Thunb.) were analyzed in Beijing for 22 rainfall events (2.4–46.4 mm) from 1 July to 30 September 2017. Differences between minimum inter-event dry periods, module scales, substrate hydraulic conductivity and depths, drainage layer ty...

The urban stormwater management philosophy named sponge city (SPC) was put forward in 2014 as a comprehensive stormwater management strategy in China. The SPC development involves the source control measurements similarly to low impact development or green infrastructure (LID or GI) practices; the urban pipe/channel drainage system dealing with the...

Estimating sediment deposition in a stream, a standard procedure for dealing with aggradation problem is complicated in an ungauged catchment due to the absence of necessary flow data. A serious aggradation problem within an ungauged catchment in Alabama, USA, blocked the conveyance of a bridge, reducing the clearance under the bridge from several...

The rainwater retention and peak flow reduction effect of seven extensive green roof (EGR) modules were studied in Beijing under natural rainfall events from May to September 2015. Monitored EGR modules had a layer of vegetation widely planted in northern China and a substrate layer with a thickness of 20 or 50 or 100 mm. The EGRs effectively retai...

The particle tracking method (PTM) module was added into the open source Full Shallow-Water equations for Overland Flow in a two-dimensional (FullSWOF_2D) program, which has coupled rainfall–runoff and infiltration modules to determine the time of concentration (Tc) for impervious (Tci) and pervious (Tcp) surfaces. The updated program FullSWOF-PTM...

Low permeability clay-sand mixtures are often used to construct hydraulic barriers to prevent contaminated water leaching from landfills and other waste disposal sites from polluting local groundwater aquifers. In order to engineer effective hydraulic barriers, a proper knowledge of the hydraulic conductivity of clay-sand mixtures is required. Whil...

Quantification of the uncertainty associated with stormwater models should be analyzed before using modelling results to make decisions on urban stormwater control and management programs. In this study, the InfoWorks Integrated Catchment Modelling (ICM) rainfall-runoff model was used to simulate hydrographs at the outfall of a catchment (drainage...

A calibrated three-dimensional environmental fluid dynamics code model was applied to simulate temperature distributions under various hypothetical weather conditions and daily repeated large releases (DRLRs) from the upstream boundary in a river-reservoir system in Alabama. Both the duration of DRLRs and weather conditions affect and control the f...

Heavy metals from urban stormwater runoff are important sources of surface water pollutants. Sand, zeolite, sandy loam, and quartz-sand were separately mixed with lignin to form four bioretention media mixes for experimental study using synthetic stormwater runoff. The average removal efficiencies of four heavy metals (Cu, Zn, Cd, and Pb) by the fo...

Water quality and fish habitat models were developed and applied to investigate impacts of future climate change on cisco oxythermal habitat in Minnesota lakes. Long-term daily water temperature (T) and dissolved oxygen (DO) profiles were simulated for different types of representative lakes (surface area from 0.05 to 50 km2) in Minnesota under the...

Climate disrupts aquatic ecosystems directly through changes in temperature, wind, and precipitation, and indirectly through watershed effects. Climate-induced changes in northern lakes include longer ice-free season, stronger stratification, browning, shifts in algae, and more cyanobacterial blooms. We compared retrospective temperature-depth rela...

Cisco (Coregonus artedi) is the most common coldwater stenothermal fish in Minnesota lakes. Water temperature (T) and dissolved oxygen (DO) in lakes are important controls of fish growth and reproduction and likely change with future climate warming. Built upon a previous study, this study uses a modified method to identify which of 620 cisco lakes...

A two-dimensional hydrodynamic CE-QUAL-W2 model was configured for a deep subtropical river-run reservoir, the Xiluodu Reservoir (XLDR), in China to simulate water temperature in the first two years of impoundment (2013-2014) using measured data as model input. It was calibrated using observed temperature profiles near the dam and the outflow tempe...

For urban land development, some or all natural land uses (primarily pervious) are converted into impervious areas which lead to increases of runoff volume and peak discharge. Most of the developed countries require a zero increase in peak discharge for any land development, and the policy has been implemented for several decades. The policy of zer...

Sediment runoff rates from construction sites can be substantially higher than those of other land uses. Construction stormwater regulations require detailed stormwater pollution prevention plans to minimize environmental impacts associated with construction activities. Sediment basins are temporary sediment control measures used to detain and trea...

Temperature distribution in a river-reservoir system was simulated using a calibrated three-dimensional Environmental Fluid Dynamics Code model under various hypothetical weather conditions and daily repeated large releases (DRLRs) from the upstream boundary. Both DRLRs and weather conditions affect and control the formation and spread of density c...

Erosion and sediment control products have become an integral part of the construction industry as manufacturers now provide innovative alternatives to traditional practices. Ditch checks are used on construction sites to intercept channelized stormwater runoff to reduce flow velocity, minimize channel erosion, and promote sedimentation. A standard...

Fish habitat in lakes is strongly constrained by water temperature (T) and available dissolved oxygen (DO) that are changed under climate warming. A one dimensional, dynamic water quality model MINLAKE2012 was used for T and DO simulation over 48 years. A fish habitat model FishHabitat2013 using simulated T and DO profiles as input was developed to...

An urban rainfall-runoff water quality model was developed to simulate total suspend solids (TSS) using the stormwater management model (SWMM) for a 3.8 ha university campus in Beijing (approximately 76.5% impervious), and calibrated and validated against data from two observed rainfall events (221.2 and 16.6 mm rainfall). Model performance is sati...

Air temperature is often used to estimate stream water temperature by developing regression models. A method using modified sine functions and sinusoidal wave functions (MSSWF) was proposed for estimating hourly water temperatures in rivers. Estimates of daily maximum and minimum water temperatures from sine functions (SFs) were corrected using lin...

Stormwater regulations require construction-generated pollution to be controlled on-site prior to discharge to avoid impairment of receiving waterbodies. Sediment basins are stormwater detention practices commonly used to capture and treat sediment-laden runoff prior to discharging from a construction site. Federal and state highway and environment...

Various problems such as urban flood inundation and water shortage occurred in China during the rapid urbanization in the last several decades. An urban water management program called Sponge City (SPC) is put forward in China in 2014 in order to relieve the flood inundation and water shortage situation. The SPC program implements not only the conc...

Water temperature is a critical variable for water quality control and management. Air temperature is often used to estimate stream water temperature by developing regression models. Two direct regression models between hourly water and air temperature were developed for 8 rivers in Alabama and have reasonable model accuracy. The second method usin...

A three-dimensional environmental fluid dynamics code model was calibrated and applied to simulate unsteady flow patterns, dye distributions and concentration in the Bankhead River-Reservoir System in Alabama, USA. A series of sensitivity model runs were performed under different large releases (140 m³/s) from Smith Dam Tailrace (SDT) when other in...

Construction-related activities typically disturb established vegetation, resulting in the potential for accelerated erosion. Because of the associated water quality impacts of construction activities, the USEPA has established regulatory programs to manage stormwater runoff emanating from construction sites. Currently, designers typically rely on...

A calibrated three-dimensional Environmental Fluid Dynamics Code model was applied to simulate unsteady flow patterns and temperature distributions in the Bankhead river-reservoir system in Alabama, USA. A series of sensitivity model runs were performed under daily repeated large releases (DRLRs) with different durations (2, 4 and 6 h) from Smith D...

A three-dimensional flow and temperature model was applied for a 124 km river-reservoir system from Lewis Smith Dam tailrace to Bankhead Lock & Dam, Alabama. The model was calibrated against measured water levels, temperatures, velocities and flow rates from 4 May to 3 September 2011 under small constant release (2.83 m³/s) and large intermittent r...