Constructed wetlands for the treatment of landfill leachates: The Slovenian experience

Constructed wetlands are widely recognized as an economical, efficient and environmentally acceptable means to treat many different types of wastewater. Six systems have been constructed in Slovenia for the treatment of landfill leachates. This paper describes the early stages of two treatment systems operating from 1990 to 1993 that were used to treat leachates from municipal landfills. System S1 consisted of a sedimentation lagoon and a 600 m² reed bed. System S2 was designed with a sedimentation lagoon and two reed beds (total=450 m²). The subsurface flow in both was horizontal and fluctuated widely in S2, but was a constant 0.2 1 s^–1 in S1. Peat, soil, sand and gravel were in system S2, while gravel with a hydraulic conductivity of 5×10^–4 m s^–1, was in S1.The unanticipated fluctuations of hydraulic and organic loadings influenced their performance. The efficiency in reduction of organic matter, N, P, metals and fecal coliforms varied through the year. In 3 years of operation, the average removal efficiencies for COD, BOD₅ and TSS were 38%, 61%, and 81%, respectively, in S1, and 53%, 45%, and 47%, respectively, in 1.5 years of operation for S2. The reduction of ammonium did not reach the effluent standard of 10 mg l^–1 for either S1 or S2. As, Zn, Pb, and Cu accumulated in roots, and Cu, Fe, As, Ni and Pb accumulated in rhizomes after one year of operation in S2.     

Seasonal and annual performance of a full-scale constructed wetland system for sewage treatment in China

A full-scale constructed wetlands system with a total area of 80 ha and treatment capability of 2.0 × 10⁴ m³ d⁻¹ was completed in October 1998 in Rongcheng, Shandong Province, China. To evaluate wastewater treatment effectiveness and seasonal performance of the system, water samples were collected and analyzed from January 1999 to December 2004. Comparison of mean inlet and outlet concentrations showed that the constructed wetland system could effectively reduce the output of SS (71.8 ± 8.4%), BOD₅ (70.4 ± 9.6%), COD (62.2 ± 10.1%), total coliform (99.7%) and fecal coliform (99.6%). However, the percent reduction of ammonia nitrogen was relatively low (40.6 ± 15.3%), and total phosphorus showed the least efficient reduction (29.6 ± 12.8%). BOD₅, COD, ammonia nitrogen, and total phosphorus removal efficiencies displayed seasonal variations. BOD₅ and COD removal was more efficient in spring and summer than in autumn and winter whereas ammonia nitrogen and total phosphorus removal was more efficient in summer and autumn than in spring and winter. Annual variation analysis shows that COD, BOD₅, and ammonia nitrogen reduction efficiencies increased from 1999 to 2004. In contrast, mean total phosphorus reduction efficiency did not change from 2001 to 2002 and began to decrease from 2003 onwards.     

Subsurface-flow constructed wetlands in Spain for the sanitation of small communities: A comparative study

In comparison with other European countries, constructed wetlands may still be considered a recent technology in Spain. A survey of the systems treating urban wastewater in this country revealed that over 80% of subsurface-flow constructed wetlands have been built over the last 5 years, horizontal systems (HF-CW) alone or in combination with other unit processes such as ponds being the most widespread type. Organic loads ranged from 0.8 to 23, from 22.8 to 29.8 and from 3.6 to 16.7 g BOD m⁻² day⁻¹ for HF-CW (alone), vertical systems (VF-CW) and combined systems (HF-CW with other unit processes), respectively. The performance of such systems in terms of BOD₅ removal generally ranged from 80 to 95% in all cases (HF-CW, VF-CW and combined systems), whereas COD removal was slightly lower, ranging from 50 to 95%, 80 to 95% and 50 to 90% for the HF-CW, VF-CW and combined systems, respectively. Furthermore, the TSS removal rate ranged from 70 to 95% for combined systems and from 85 to 95% for HF-CW (alone). The systems were not very efficient in terms of nutrient removal (nitrogen and phosphorus), with total average removal efficiencies around 40–50%. In general terms, the analysis of constructed wetlands in Spain shows that although they operate with higher loads than in other European systems, their performance in terms of organic matter and nutrient removal is in the range of that described in previous studies.     

Improving water quality in polluated drains with free water surface constructed wetlands

In Egypt, disposing of partially treated or untreated domestic and industrial wastewater into agricultural drains deteriorates their water quality. A growing interest in effective low-cost treatment of polluted water and wastewater has resulted in many studies on constructed wetlands.This study evaluates free water surface constructed wetlands (by far the largest application project is named “Lake Manzala Engineered Wetland [Egypt]”) utilized to improve the water quality in Bahr El Baqar drain, which is located at the northeastern edge of the Nile Delta. This drain discharges its water into Manzala Lake, which in turn has many fishing activities and is connected to the Mediterranean Sea. The full capacity of the constructed wetland system is 25,000 m³/day. Three various flow rate wetlands were investigated; five wetland beds of high flow rate of 0.344 m³/m²-day, five wetland beds of low flow rate of 0.048 m³/m²-day and reciprocated cells of flow of 500 m³/day.The concentrations of different contaminants along the constructed wetlands system were measured to determine the treatment efficiency. The effluent was compared with the Egyptian standards of water quality in agricultural drains (Law 48/1982). Due to the high percentage of the agricultural water drain, the concentrations of contaminants in the influent were relatively low. The percentages of removal for the different contaminants were BOD₅: 52%, COD: 50%, TSS: 87%, TDS: 32%, NH₄-N: 66%, PO₄: 52%, Fe: 51%, Cu: 36%, Zn: 47% and Pb: 52%. The natural vegetation considerably increased the value of dissolved oxygen in the treated effluent. There were little differences in the removal efficiency between the high and low flow rates beds in the system.     

Municipal wastewater treatment with vertical flow constructed wetlands for irrigation reuse

The treatment effect of two pilot-scale vertical flow constructed wetlands (VFCWs) on municipal wastewaters and their suitability for irrigation reuse were evaluated in a 2-year (2002–2003) experiment. One VFCW was planted with Typha latifolia and the other with Phragmites australis. VFCW efficiency was evaluated in terms of both mass removal and water quality improvement, considering the following parameters: pH, electrical conductivity (EC_w), total suspended solids (TSS), chemical oxygen demand (COD) and biochemical oxygen demand (BOD), total nitrogen (TN) and nitrate (NO₃^?), total phosphorus (TP) and orthophosphate (PO₄^3?), sodium (Na), potassium (K), magnesium (Mg) and calcium (Ca). The accumulation of the elements in the plant organs and VFCW sandy surface layer and their offtake with the macrophyte harvest were also measured.In quantitative terms the established VFCWs showed higher removal efficiencies (>86%) for COD, BOD, N and K, while lower efficiencies (<47%) were observed for Na and Mg. The direct contribution (offtake) of the macrophytes in N, P and K removal processes was particularly high (>65%) due to the massive growth. The results were less favourable in terms of water quality, because the high evapotranspiration losses counteracted the depuration process by concentrating the elements in the outflow water. Higher concentrations were found in outflow than inflow, especially of Na (relative increase of 89%) and Mg (relative increase of 74%). Only parameters with high removal efficiencies fulfilled the Italian guidelines for irrigation reuse whereas parameters with lower efficiencies (e.g., TSS, TP) limited the potential water reuse. Efficient pre-cleaning systems or innovative integrated systems are thus necessary to obtain high removal efficiencies that reduce the effect of ET on water quality.     

Kinetics of pollutant removal from domestic wastewater in a tropical horizontal subsurface flow constructed wetland system: Effects of hydraulic loading rate

The treatment capacity of constructed wetlands is expected to be high in tropical areas because of the warm temperatures and the associated higher rates of microbial activity. A pilot scale horizontal subsurface flow constructed wetland system filled with river sand and planted with Phragmites vallatoria (L.) Veldkamp was set up in the southern part of Vietnam to assess the treatment capacity and the removal rate kinetics under tropical conditions. The system received municipal wastewater at four hydraulic loading rates (HLRs) of 31, 62, 104 and 146 mm day^?1. Removals of TSS, BOD₅ and COD were efficient at all HLRs with mean removal rates of 86–95%, 65–83% and 57–84%, respectively. Removals of N and P decreased with HLRs and were: NH₄-N 0–91%; TN 16–84% and TP 72–99%. First-order area-based removal rate constants (k, m year^?1) estimated from sampling along the length of the wetland from inlet to outlet at the four HLRs were in the range of 25–95 (BOD₅), 22–30 (COD), 31–115 (TSS), 5–24 (TN and TKN) and 41–84 (TP) at background concentrations (C*) of 5, 10, 0, 1.5 and 0 mg L^?1, respectively. The estimated k-values should not be used for design purposes, as site-specific differences and stochastic variability can be high. However, the study shows that domestic wastewater can be treated in horizontal subsurface flow constructed wetland systems to meet even the most stringent Vietnamese standards for discharge into surface waters.     

Comparison of the treatment performances of blast furnace slag-based and gravel-based vertical flow wetlands operated identically for domestic wastewater treatment in Turkey

In 2001, to foster the practical development of constructed wetlands (CWs) used for domestic wastewater treatment in Turkey, vertical subsurface flow constructed wetlands (30 m² of each) were implemented on the campus of the METU, Ankara, Turkey. The main objective of the research was to quantify the effect of different filter media on the treatment performance of vertical flow wetlands in the prevailing climate of Ankara. Thus, a gravel-filled wetland and a blast furnace granulated iron slag-filled wetland were operated identically with primarily treated domestic wastewater (3 m³ d⁻¹) at a hydraulic loading rate of 0.100 m d⁻¹, intermittently. Both of the wetland cells were planted with Phragmites australis. According to the first year results, average removal efficiencies for the slag and gravel wetland cells were as follows: total suspended solids (TSS) (63% and 59%), chemical oxygen demand (COD) (47% and 44%), NH₄⁺–N (88% and 53%), total nitrogen (TN) (44% and 39%), PO₄³⁻-P (44% and 1%) and total phosphorus (TP) (45% and 4%). The treatment performances of the slag-filled wetland were better than that of the gravel-filled wetland in terms of removal of phosphorus and production of nitrate. Since this study was a pioneer for implementation of subsurface constructed wetlands in Turkey using local sources, it has proved that this eco-technology could also be used effectively for water quality enhancement in Turkey.     

Mountain cheese factory wastewater treatment with the use of a hybrid constructed wetland

This paper describes the activity period of an experimental hybrid wetland system placed in a cold climate region. The aim is to determine the efficiency of the system in reducing TSS, BOD₅, COD and other pollutants. The constructed wetland consists of a fat-removal unit and a basin for the storage and the distribution of the wastewater which precedes three phytoremediation beds: the first two are parallel and they work as submerged vertical flow wetland with gravel medium for an area of 180 m²; the last is a submerged horizontal flow wetland with sand medium and an area of 360 m². The CW was designed to process a total estimated BOD₅ loading rate of about 24 g m⁻² d⁻¹, which was less than half of the average actual loading rate. The wastewater treatment did not meet the required Italian law outflow limits, most likely due to BOD₅ overloading.     

Polishing low-biodegradable and saline industrial effluent in a full-scale horizontal subsurface flow constructed wetland: evaluation of bio-treatability and predictive power of kinetic models

Abstract

This study evaluates the bio-treatability performance and kinetic models of full-scale horizontal subsurface flow constructed wetland used for the tertiary treatment of composite industrial effluent characterized by high-salt content ranging from 5830 to 10,400 µS/cm and biochemical oxygen demand (BOD₅): chemical oxygen demand (COD) ratio below 0.2. The wetland vegetated with Phragmites australis was operated in a semi-arid climate under an average hydraulic loading rate of 63?mm/d. The results of a 4-year operation calculated based on the concentration of pollutants showed that the average removal efficiency of COD, BOD_5, and total suspended solids (TSS) were 17.5, 5.1, and 11.2%, respectively. The system reduced up to 6.5?±?0.7% of electrical conductivity presenting poor phyto-desalination potential without considering the contribution of evapotranspiration in water balance in contrast to satisfying performance for heavy metals reduction. The comparison of the kinetics of organic matter removal obtained by the first-order and Monod models paired with continuous stirred-tank reactor and plug flow regime showed that Monod-plug flow model provided the best fit with the constants of 2.01?g COD/m²·d and 0.3014?g BOD₅/m²·d with the best correlation coefficient of 0.610 and 0.968 between the predicted and measured concentrations, respectively. The low kinetic rates indicate that the process is capable of effluent polishing instead of purification due to the presence of organic compounds recalcitrant to biodegradation and a high level of salinity.     

A new approach in wetland systems for domestic wastewater treatment using Phragmites sp.

The conventional wetland system using Phragmites sp. is in existence since 20 years. The constructed wetland system has not gained much popularity due to large land area requirement, clogging of beds and need for capital investment. The aim of the study is to develop a new approach to the horizontal flow wetlands system (termed bio-rack) for treatment of domestic wastewater. The new system dealt with an engineered attached growth matrix and a high microbial degradation rate. The study on bio-rack was undertaken in a horizontal flow pilot plant using Phragmites sp. and experiments were carried out for various parameters. Analytical data were collected during the studies which include temperature, pH, chemical oxygen demand (COD), biological oxygen demand (BOD₅), dissolved oxygen (DO), chlorides, total dissolved solids (TDS), total suspended solids (TSS), ammonia nitrogen (NH₃-N), phosphate (PO₄-P) and most probable number (MPN). This paper also studies microbial flora present in the system by isolating and identifying the microorganisms, and also measuring total viable count (TVC). Morphological aspects with reference to the growth of plant were studied and it indicated high plant yield. At optimum hydraulic retention time (HRT) of 10 h, approximately 75.15% COD, 86.59% BOD₅, 27.54% TDS, 73.13% TSS, 8.86% Chlorides, 70.22% NH₃-N, 31.71% PO₄-P and 92.11% MPN reduction was achieved in bio-rack system. A comparative evaluation was done with the conventional wetland system and better treatment efficiency was observed in the bio-rack system. This result indicates a possibility of development of a substantially effective system compared to any other methods on constructed wetland.     

Constructed wetlands with free water surface for treatment of aquaculture effluents

The aim of the study was to determine the reduction of the overall environmental load (in terms of organic and nutrient load) in effluents of a flow‐through trout farm. Effluents of a flow‐through system for rainbow trout (Oncorhynchus mykiss) production passed through constructed wetlands with free water surface. Removal of nutrients was determined in three wetlands of 350 m² each at hydraulic residence times (HRTs) of 3.5, 5.5 and 11 h. The areal load of total suspended solids (TSS), chemical oxygen demand (COD), total phosphorus (TP), and total nitrogen (TN) varied in terms of HRTs from 12.3–36.8 g m^?2 day^?1, 21.7–65.2 g m^?2 day^?1, 0.23–0.70 g m^?2 day^?1, and 1.46–4.37 g m^?2 day^?1. Values for reduction of suspended solids, COD, TP, and TN were 67–72%, 30–31%, 41–53% ,and 19–30%, respectively. Significantly lower nutrient concentrations in the effluent among the wetlands were only found for nitrogen parameters: TN and ammonia concentrations were lower in the wetlands with a HRT of 5.5 h (0.89 mg L^?1, 0.11 mg L^?1) and 11 h (0.81 mg L^?1, 0.11 mg L^?1) compared with the one with 3.5 h (0.96 mg L^?1, 0.16 mg L^?1).     

Generating “Tide” in Pilot‐Scale Constructed Wetlands to Enhance Agricultural Wastewater Treatment

The operation of tidal flow was studied using a pilot‐scale system treating high strength piggery wastewater. Located on a farm in Staffordshire, UK, the system consisted of five wetland treatment stages vegetated with common reeds of Phragmites australis. Wastewater samples were collected from the inlet and outlet of each stage and analyzed for BOD₅, COD, NH₄‐N, NO₃‐N, NO₂‐N, SS, PO₄‐P and pH. Average hydraulic and organic loadings on the system were 0.12 m³/m² d and 240 g BOD/m² d, respectively, which is considerably higher than the typical loadings on conventional subsurface flow systems. On average, BOD₅ and COD were reduced by 82 % and 80 % from initial concentrations of 2000 mg/L and 2750 mg/L, respectively, across the whole system. The first‐order kinetics constant for BOD₅ removal (K_BOD in m/d) in this tidal flow system is approximately 2.5 times the rate constant obtainable in a typical horizontal flow system, demonstrating a more efficient removal of organic matter in tidal flow wetlands. The overall efficiency of the system was found to increase with time before stabilizing towards the end of a start‐up period. Straight‐line correlations were established between the loading and removal of BOD₅ and COD. Contributions by individual stages to the overall treatment were analyzed. SEM images of wetland media demonstrated the formation of biofilms and microbial activities inside the matrices of the wetland system, which accounted for the degradations of organic pollutants.     

Factors influencing the efficiency of constructed wetlands used for the treatment of intensive trout farm effluent

In this paper the factors influencing treatment performance of subsurface flow constructed wetlands (SSF wetlands) treating aquaculture effluents were identified and quantified. The financial impact of advanced aquaculture effluent treatment with SSF wetlands was calculated.It is the first long-term, commercial-scale trial of SSF wetland treatment for effluents from intensive trout farming, a highly diluted effluent at very high flow rates (mean total phosphorous concentration 0.34 mg L^?1 at 14.3 L s^?1). The 12-month survey provided the opportunity to generate calculation fundamentals for the commercial application of SSF wetlands for aquaculture. Treatment efficiencies of up to 75–86% for total ammonia nitrogen (TAN), biological oxygen demand (BOD₅) and total suspended solids (TSS) were achieved. The daily area retention rate per square meter wetland area was between 2.1 and 4.5 g for TAN and between 30 and 98 g for TSS.The performance of the six wetland cells comprising three replicated hydraulic loading groups (14.5, 6.9, 3.3 m³ m^?2 day^?1) was monitored, offering the possibility to identify factors influencing treatment efficiency through multifactor analysis. These factors turned out to be nutrient inflow concentration, hydraulic loading rate and accumulation of TSS within the wetland bed, the only time-dependent factor. Factors such as vegetation period and fish harvesting were shown to be of significant but negligible importance.Inflow nutrient concentration is determined by production intensity, husbandry conditions, feed quality and any pre-treatment of effluent. Hydraulic load is determined by the space and budget available for SSF construction. TSS accumulation in the wetland is influenced by pre-treatment of the solid fraction prior to the wetland and determines the wetland service lifetime.From these factors the expenses of commercial wetland application can be estimated, leading to a cost increase around €0.20 kg^?1 fish produced (less than 10% of production costs) and therefore confirm the commercial feasibility of SSF wetland treatment.     

Evaluation of an on-site pilot static granular bed reactor (SGBR) for the treatment of slaughterhouse wastewater

An on-site pilot-scale static granular bed reactor (SGBR) system was evaluated for treating wastewater from a slaughterhouse in Iowa. The study evaluated SGBR reactor suitability for slaughterhose wastewater having high particulate COD concentration (7.9 ± 4.3 g COD/L) at 0.3–1.4 m³/m²/day of the surface loading rates. High organic removal efficiency (over 95% of TSS and VSS removal) was obtained due to the consistent treatability of SGBR system during operation at HRTs of 48, 36, 30, 24, and 20 h. The average effluent TSS, VSS, COD, soluble COD, and BOD₅ concentrations were 84, 71, 301,197, and 87 mg/L, respectively. An effective backwash procedure was performed once every 7–14 days to waste a portion of the accumulated solids in the system. This procedure limited the increase in hydraulic head loss and maintained the system stability. COD removal efficiencies greater than 95% were achieved at organic loading rates ranging from 0.77 to 12.76 kg/m³/day.     

Rehabilitation by constructed wetlands of available wastewater treatment plant in Sakhnin

In rural areas, insufficient wastewater treatment often causes serious environmental problems, especially for human health. Due to this problem, new wastewater treatment plants (WWTP) should be constructed or upgraded. When considering economic and maintenance factors, constructed wetlands (CWs) are more desirable processes. The available WWTP located in the Northern Israeli town of Sakhnin was redesigned and upgraded. To rehabilitate the WWTP, six new CWs having different operating conditions were constructed as a pilot project. The most appropriate place of construction of the CWs was thought to be at the end of the WWTP. From the beginning of the system, inlet and outlet pollution parameters such as chemical oxygen demand (COD), ammonia (NH₄-N⁺), total suspended solids (TSS), and phosphorus (PO₄-P³⁻) were monitored in the CWs from August 2005 to February 2006. As a result the most appropriate CWs were found having Phragmites as plant and volcanic tufa as media material. The maximum removal efficiencies were 71.8% on COD, 92.9% on TSS, 63.8% on ammonia for CW5 tank. Adversely, phosphorus removal was not so high in CW5. Phosphorus removal was negligible in the study.     

Performance of an anaerobic baffled reactor and hybrid constructed wetland treating high-strength wastewater in Nepal—A model for DEWATS

Centralized wastewater treatment systems require sophisticated technologies and skilled manpower for their operation and maintenance (O&M). These systems have huge construction as well as O&M costs. Therefore, a Decentralized Wastewater Treatment System (DEWATS) rather than a centralized system might be especially beneficial in developing countries. A model for DEWATS is developed in Nepal with Anaerobic Baffled Reactor (ABR) and hybrid Constructed Wetland (CW). The DEWATS treats high-strength wastewater from 80 households (400 PE). This paper summarizes the performance of the DEWATS from July 2006 to August 2007 in the removal efficiencies of TSS, BOD₅, COD, NH₄–N, TP and FC. The ABR is very effective in the removal of organic pollutants and could achieve TSS removal up to 91%, BOD₅ up to 78% and COD up to 77%. The average removal efficiencies of the DEWATS is 96% TSS, 90% BOD₅, 90% COD, 70% NH₄–N, 26% TP and 98% FC.     

Long term performance of a constructed wetland for landfill leachate treatment

The constructed wetland (CW) was developed as a pilot integrated system for the capital city's old sanitary landfill site. It consisted of three interconnected beds, two of vertical flow and one of horizontal flow stage. The CW covered 311 m² with an intermittent hydraulic load of 0.5 cm d⁻¹, filled with sand media and planted with reeds and cattails. The performance efficiency of the CW systems was evaluated for 7 years through physical and chemical parameters. Some monitored parameters varied noticeable. The efficiency for COD was 50%, BOD₅ (59%), ammonia nitrogen (51%), nitrate (negative), total phosphorus (P) (53%), sulfates (negative), sulfides (49%), chlorides (35%), and Fe (84%). The average concentrations of suspended solids, COD, BOD₅, nitrate, total P, sulfates, sulfides, and Fe were below limits after treatment. The ratio between N and P showed a limited level of P for biological processes. The performance of the system did not vary significantly with regard to temperature, however, it varied with precipitation. The results showed that the CW system, as a tertiary system or as an independent system, could be a low-cost alternative for the treatment of leachate from old landfill sites.     

Solids hydrolysis and accumulation in a hybrid anaerobic digester-constructed wetlands system

The properties and behaviour of solids retained in a pilot plant constituted of an up-flow anaerobic sludge blanket (UASB) reactor and two constructed wetlands (CWs) were monitored over a 3-year period. The UASB (25.5 m³) was fed with raw municipal wastewater at a flow rate of 61–112 m³ d^?1 and a volumetric loading rate (VLR) of 0.75–1.70 kg TCOD m^?3 d^?1. The CWs (75 m² each) were operated in series and received a fraction (17–20 m³ d^?1) of the UASB effluent. The applied surface loading rates (SLR) were in the range of 3800–8700 g TCOD m^?2 d^?1 (UASB) and 11–15 g BOD₅ m^?2 d^?1 (CWs). The overall system removed 95% TSS, 85% TCOD and 87% BOD₅ on average. For influent VSS, the UASB removed 72.1% and gave a hydrolysis of 63.5%, while the average surplus sludge generation was 8.7%. Over the 3-year period, TSS and VSS accumulated in the CWs at rates of 1.07 and 0.56 kg m^?2 year^?1, respectively. The aerobic biodegradability of the accumulated solids ranged from 23 to 92 mg O₂ g VSS^?1 d^?1 and increased downstream in the CWs. About 59% of the VSS that entered the CWs was removed by hydrolysis, while 24% accumulated on granular media. These low solids accumulation rates were especially remarkable considering the high COD and BOD₅ loading rates applied. The system lay-out appear to be promising in terms of preventing clogging.     

Study on ecological protection and rehabilitation technology of a reservoir-type water source in the northeastern region of China

ABSTRACT

Surface water is the main source of water for human life and production. The quality of water affects living conditions and the overall health of people. Ecological protection and restoration engineering technology, combining ecological revetment and an ecological floating bed, is applied to a selected shallow beach experimentation area of a reservoir water source area in Northeast China. According to local conditions, the ecological revetment plants were identified as Goosegrass, sedges, and water grasses, and other local species of Polygonum hydropiper bagen, reeds, and bulrushes were identified as ecological floating bed plants. Regular monitoring of water quality in the experimentation area and a control area showed that the ecological protection and restoration technology can effectively reduce the concentrations of BOD₅ (five day biochemical oxygen demand), COD (chemical oxygen demand), TN, NH₃-N, NO₃^?-N, TP, TDP, Mn, Zn, Fe, Pb, total coliforms, and other indicators of surface water in the experimentation area. The BOD₅, COD, Max TN, NH₃-N, NO₃^?-N, TP, and TDP reduction rates were 84.76%, 57.14%, 86.76%, 83.78%, 89.26%, 94.02%, and 95.89%, respectively, with the implementation of water pollution prevention and the purifying shoal.