Skip to main content

Hitachi

Water Environment Solutions

Overview

General issues of groundwater utilization

  1. It is difficult to grasp the 3-D structure of aquifer using only the information available from wells.
  2. Over-extraction of groundwater causes environmental deterioration such as drying up of lakes, land subsidence and water salinization.

Environmental changes due to extraction


Drying up


Land subsidence


Water salinization

The use of WCSS *1 (Water Cycle Simulation Service)

  1. Makes it possible to quantify the objective groundwater system.
  2. Could provide forecasts of change of environmental changes under assumed scenarios of pumping, such as drying up, land subsidence and water salinization.
*1)
WCSS is developed technologies through technical cooperation by Geosphere Environment Technology Corp.

System Configuration

Analysis procedure is (1) data collection/compilation, (2) modeling and simulation, (3) calibration, (4) forecasting and reporting.

Features

Analysis with 3D-GIS (Geographic Information System) visualization enables observation understanding of current water balance, potential water volume of groundwater, and salinity state.

  1. WCSS can simultaneously trace the flows of surface water and groundwater
    The most prominent feature of the WCSS used here is the function that enables fully joined treatment of surface and subsurface water flows. In the simulation, the interaction of waters on the surface and subsurface is determined by the difference of hydraulic potentials of the peripheral points, so that downward infiltration, upward gushing, and the flow along the surface are modeled naturally and physically.
  2. Visualization of the simulated results by graphics overlaid on GIS is possible.
    As an example, WCSS is able to analyze and visualize (1)streamline indicating the trace of the water flow, (2)the flow quantity that shows the water amount, (3)flow direction of groundwater, (4)distribution of the ground water level, and the salinity distribution in order to understand the border between fresh water and salt water.
  3. Advantage for Brackish Water RO and Seawater RO
    (1)Survey cost reduction (Brackish Water RO) *2
    WCSS helps reduce the number of surveys compared to conventional plans by narrowing down the survey points such as pumping tests.

    (2)Water cost reduction (Brackish Water RO/Seawater RO) *3
    • Seawater RO : Simulating the volume and salinity of the groundwater in inland areas
    • Brackish Water RO : Simulating the volume and salinity of the groundwater in the sea bottom spring water area of coastal area.
    Cost can be reduced by selecting an area where low salinity water can be stably extracted.

    (3)Forecast (Brackish Water RO/Seawater RO)
    WCSS helps in evaluating the environmental impact and the risk of increasing the facility operation cost, based on scenario studies.
    • Scenario A : Draining of water, land subsidence and water salinization by over extraction
      Evaluation item : Groundwater volume, level and salinity
    • Scenario B : Drain of water by change of weather conditions
      Evaluation item : Groundwater volume and level
    • Scenario C : Increase of Brackish Water RO facilities in the neighborhood
      Evaluation item : Groundwater volume and level
    *2)
    RO : Reverse Osmosis

(In-house comparison)

Application

  • For predicting future droughts and developing new water resources by scenario analysis
  • For selecting sites for sea water desalinization plant
  • For planning alternative water resources to ease land subsidence by overextraction of groundwater