The SWAN is responsible for works related to land subsidence; some of them include the investigation of seawater intrusion, surveys for land subsidence factors, inventory of wells, land subsidence trends along the High Speed Rail (HSR), groundwater recharge mechanisms and promotion, etc. Results and descriptions of works and projects as follows:

Investigation results of the groundwater recharge mechanisms:

1.Analysis of the traditional hydrogeological parameters obtained by in-situ tests (Zhutang) and accuracy comparisons of the hydraulic conductivity, as reference for the evaluations of the groundwater recharge mechanisms.

2.Producing mechanisms for groundwater recharge based on on-site tests and evaluations for water quantity by using groundwater recharge shafts for the feasibility of the groundwater conservation.

Outcomes of groundwater recharge works:

1.The SWAN has completed the first large-scale groundwater recharge facility in Taiwan, also known as the “Chou-Shui river groundwater recharge facilities”. For the counties of Changhua and Yunlin, the SWAN suggested that by building a dam on the Shia-Shou-Pu reach, an artificial lake at the apex of the Chou-Shui alluvial fan and a storage facility on the northern bank of the Chou-Shui river floodplain, the groundwater recharge volume of the Chou-Shui river alluvial fan can be increased and the effects of land subsidence can be reduced. For its innovative development and effective groundwater recharge results, this work can be used as a reference for future related works in Taiwan or in other counties.

2.For the groundwater recharge performance of the flood prone areas in the Chou-Shui river alluvial fan, the SWAN has completed a research, based on a 10-year rainfall data project and on actual rainfall data (2000-2014). The SWAN is also responsible for reports regarding the volume estimations, evaluations and results of the groundwater recharge in the counties of Yunlin and Changhua which can be used as a reference for related projects of the central government.

The SWAN is responsible for works related to the allocation of regional water resources; some of them include the construction and maintenance of the Douliou Canal water distribution model, the construction and maintenance of Cizipi Canal irrigation model, feasibility analysis for the Cho-Suei irrigation system, feasibility planning for the Gukeng artificial lake, investigation and development planning for the groundwater resources in Minzu Basin and the irrigation system of Yunlin, development planning and management of the water resources in Formosa Plastics Group (FPG) Naphtha Cracker #6 Industrial Park, land subsidence prevention works for the Chou-Shui river alluvial fan, etc. Results and descriptions of works and projects as follows:

Outcomes of the Douliou Canal water distribution model:

For the water volume consumption analysis of the Douliou Canal, the SWAN applied water balance methods as well as the agricultural concept of saving water during the nighttime off-peak hours. The results showed that 2,772 Megatons of water can be saved annually. Moreover, 2,197 Megatons of water to be saved by reducing the pumped water usage by 757 Megatons. This quantity is enough to supply all the drought areas of Yunlin through the Douliou Canal irrigation system.

Outcomes of the feasibility plan for the Gukeng artificial lake:

The SWAN was responsible for the research development, the construction and the work processes of the Gukeng artificial lake. The management and all the operations were planned based on the "Research and Recommendations for Reservoir Management: Human Resources, Operations and Maintenance" framework.

Investigation and development planning for the groundwater resources in Minzu Basin:

In order to confirm the adequate volume of the groundwater resources and the potential for further development of the Minzu Basin, the SWAN investigated all the necessary data (hydrogeological, river flow, groundwater level data, etc.) as well as the data obtained from the in-situ tests for analysis and simulation. The results showed that the development of an underground reservoir in the Minzu Basin is feasible.

Investigation and development planning for the irrigation system of Yunlin:

By assisting the Yunlin Irrigation Association, the SWAN investigated the irrigation and water supply system in comparison to the demand statuses. Among other fields, emphasis was given to the irrigation sources, hydrological data, agricultural demands, etc. The results of this research contributed in the establishment of a water saving irrigation database for the agricultural demands of Yunlin and in a comprehensive analysis for an efficient and effective irrigation system based on the fair demands and needs of the consumers. Furthermore, the outcomes suggest methods for minimizing the irrational water consumption and adapting a sustainable agricultural scheme for the county of Yunlin.

Formosa Plastics Group (FPG) Naphtha Cracker #6 Industrial Park:

By completing this project, the SWAN provided solutions to the water supply and demand problems which exist for more than 50 years in the Chou-Shui river alluvial fan. The research focused on the relationship between the water consumption for industrial use in the Naphtha Cracker #6 Industrial Park, the causes of the water shortage phenomena in certain areas of Yunlin and the water consumption by groundwater pumping. The reports presented the actual water consumption of each factor as well as methods for a more efficient water consumption policy.

Hushan reservoir:

The Center used Sensefly company's UAV, including eBee and Swinglet CAM, Its specifications are as follows shown:

The Hushan reservoir was divided into 22 fly zones in order to observe the area by UAV; the total flying distance was 8.16 square kilometers.

For the Digital Surface Model (DSM) of the Hushan Reservoir, 1354 photos were taken and edited accordingly.

Chou-Shui river groundwater recharge facilities:

The SWAN uses UAV in order to inspect the status of the Chou-Shui river groundwater recharge facilities and detect possible damages of the embankments.

Investigation of hyporheic flow in Xi-Luo section of the Chou-Shui river:

By using UAV, the researchers of SWAN can estimate all the necessary parameters, such as the groundwater flow, the distance between the observation well and the watercourse, the length of the wet perimeter, etc. more accurately.

Detection and management of the pollution in Qingshui village (Lugu Township):

By assisting the Nantou County Government, Environmental Protection Bureau, the SWAN has completed a project related to soil and groundwater monitoring in order to identify all the potential sources of pollution in the Qingshui village. Furthermore, the project records and allocates all the crop species and the agricultural activities in order to detect the exact location of the pollution source. For more accurate results, the UAV was used to observe the area.

Land sliding phenomena:

The SWAN uses the UAV in order to investigate and evaluate the impacts of the land sliding as well as the environmental changes and impacts of influenced areas.

The SWAN is responsible for works related to water resources; some of them include hydrogeological surveys for all the groundwater regions of Taiwan, issuing handbooks and manuals for the investigation and the analysis of the available groundwater volume in Taiwan, the investigation and the analysis of the hyporheic flow in Taiwan, a comprehensive scheme for the investigation and the analysis of the available groundwater volume in Taiwan, etc. Researches as such, are pioneering in the fields of water resources and water survey planning and can be used as an important reference or guide not just in Taiwan but worldwide. Results and descriptions of works and projects as follows:

Hydrogeological surveys for all the groundwater regions of Taiwan:

For a comprehensive and detailed research regarding the hydrogeological surveys for all the groundwater regions of Taiwan, the SWAN has collected, investigated and analyzed vital data such as geology and terrain data, hydrogeological data, parameters of aquifers, groundwater recharge volume and location data, groundwater level changes and trends, water quality data, etc.

Handbooks and manuals for the investigation and the analysis of the available groundwater volume in Taiwan:

In order to complete this research, the SWAN investigated both domestic and foreign references so to collect and analyze all the information which can be used as a basis for this issue. This research was planned and composed based on the "Reference Manual for Investigation Analysis of the Available Groundwater Volume in Taiwan (draft)".

Handbooks and manuals for the investigation and the analysis of the hyporheic flow in Taiwan:

In order to complete this research, the SWAN investigated both domestic and foreign references so to collect and analyze all the information which can be used as a basis for this issue. This research was planned and composed based on the "Reference Manual for Investigation Analysis of the Hyporheic Flow Volume in Taiwan (draft)".

Comprehensive scheme for the investigation and the analysis of the available groundwater volume in Taiwan:

The lack of behavioral data for groundwater pumping and groundwater recharge, as well as non-accurate analysis for the available groundwater volumes lead to difficulties and obstacles for promoting effective groundwater management practices and strategies for the conjunctive utilization of surface water and groundwater. Therefore, the SWAN has created a comprehensive scheme after advising the "Investigation Analysis Scheme for the Available Groundwater Volume in Taiwan (draft)".

The SWAN is also responsible for works related to water resources in cases of emergency; some of them include the testing processes of Kuaiguan and Chutang water treatment plants, investigations and evaluations of the on-site observations for hyporheic flow in Xi-Luo section of Chou-Shui river. This research aims to provide all the necessary assistance and guidance to the government in order to adopt, plan and develop water resource policy for all the cases of emergency (e.g. extensive drought). Results and descriptions of works and projects as follows:

Outcomes of the Kuaiguan water treatment plant:

For this project, both field and empirical data were analyzed in order to build and verify a numerical model and to detect 15 potential locations for optimal well installations.

Outcomes of the Chutang water treatment plant:

The SWAN has assisted the Eleventh Branch of Taiwan Water Corporation to plan and develop a water intake facility, based on subsurface flow, on the northern shore of the Chou-Shui river floodplain near the lower and upper streams of Zichian Bridge. The numerical model simulation built for this project was able to detect the most optimal solution for a radial collector well.

Investigations and evaluations of the on-site observations for hyporheic flow in Xi-Luo section of Chou-Shui river:

For this project, related methods have been investigated in order to estimate the relationship between the surface water and groundwater in Xi-Luo section of Chou-Shui river. The results showed that the surface water and the groundwater exchange capacities appear to have similar values (0.12~0.29cms); fact which proves the representative of the hyporheic flow. Additionally, the results showed the outflow of hyporheic flow comes from the south bank, therefore all the development works were suggested to be planned accordingly.

The SWAN is responsible for works related to environmental monitoring and research. The "Hushan Reservoir Project: Downstream River of Tongtou Weir Hydrological and Environmental Monitoring" is one of them. Results and description of this work as follows:

This project focuses on the downstream rivers of Tongtou Weir; more specifically the Chinshui river and the Chou-Shui river. The simulation analysis and the influence estimations of the Tongtou Weir before and after the construction of the Tongtou Weir were based on hydrogeological data, river flow data, groundwater levels, air quality, etc., as well as related investigations and trials from the on-site hydrogeological data. This project aims to evaluate the environmental impacts of the Chinshui and Chou-Shui rivers.

The SWAN is responsible for works related to pollution, both for investigation and prevention; some of them include the water quality evaluation and analysis of hydrological stations, soil and groundwater pollution prevention in Nantou county, soil and groundwater pollution investigations along the river Erhjen, innovations for water quality, pollution investigation and prevention for the Shin-Hu-Hwei River, etc. Results and descriptions of works and projects as follows:

Outcomes of the soil and groundwater pollution prevention in Nantou county:

Since 2002, the SWAN investigates the soil and groundwater pollution and promotes related prevention strategies in Nantou County. It is estimated that more than 20 monitoring wells have been installed and according to the annual monitoring data, the water quality concentrations of the wells located in Nantou city, Lugu township, and Mingjian township have been improved. Furthermore, the soil and groundwater monitoring network in Nantou county has been upgraded and improved after establishing this long-term project.

Outcomes of the soil and groundwater pollution investigations along the river Erhjen:

For this project, the SWAN assisted the Environmental Protection Administration (EPA), Executive Yuan to complete soil and groundwater pollution investigations along the river Erhjen (Tainan county). Based on the research results, the interviews with the local communities and the field samples it was found that the soil and groundwater pollution levels of 11 sites were higher than the acceptable limits; 2 of them were even found to have extremely high pollution levels. After the completion of this research and the results provided by the SWAN, the local government was advised to act drastically and decrease the pollution levels of 6 sites along the river Erhjen so to manage this issue.

The SWAN is responsible for works related to public nuisance disputes. Such services are provided since 2008 till present. In most cases, the SWAN provides assistance to EPA; some of the responsibilities include the issuing of handbooks and manuals such as the "Managing Public Nuisance Disputes and Evaluation References for the Environmental Protection Officers" and the “Standard Operation Procedures for Public Nuisance Disputes in Case of Emergency”, updating the administrative information system (AIS) of the EPA public nuisance disputes, holding workshops and conferences for identifying and managing public nuisance disputes, etc. The goal of projects as such is to provide information and know-how to all those involved with the environment in order to boost their potential in matters of public nuisance identification and evidence collection and to reduce such phenomena.