Mapping California's Groundwater The Stanford Groundwater Architecture Project The Stanford Groundwater Architecture Project

Step 2: Develop the Data Management System

Recommendations: Development of a Data Management System

DMS chart

To determine the characteristics of a given groundwater interest area and develop a 3D hydrogeological model, many different data and datatypes are collected and interpreted together. As collecting data and compiling these into models involves several disciplines and competences hardly present in a single person or even a single organization, it is mandatory that the data are collected and stored in such a way that they are readily available and continually updated. Given the cost of acquiring the data, and the people-months spent working with the data, it is a relatively small investment to develop the DMS.

The GAP project has utilized a data management system and databases capable of storing the datatypes involved in the pilot project areas, enabling the different stakeholders to access these data across various organizations and agencies. The figure above shows the flow of data and modeling. All of the data are readily accessible through a DMS. 

An ideal process in building an HCM starts with gathering existing data and adding these to a preliminary 3D model. This allows for delineating discrepancies and uncertainties, thus identifying data gaps. Once these are identified and pointed out, new data should be collected and added to the model. In this process, all data should to be stored in a DMS. When new data are collected these data must flow into the DMS and from there be used to refine the model. This is in principle an iterative process where data gaps and uncertainties are defined and reduced with new data. The DMS will throughout this process store data revised models enabling a close cooperation between the different parties and persons involved. This has been the case in the GAP project.

The data and results of the modeling should also be available for public use, especially for authorities, GSA’s and in general for people with interest in the topic. This requires an open formats. Most data have a spatial relation, which means that maps are the common way of displaying. Open maps formats as WMS or WFS which can be used by a variety of client software must be supported. Dedicated web map applications tailored to this purpose are very useful for public outreach. 3D applications able to visualize the often complex hydrogeologic settings are also useful in communicating results.

DMS on a Regional/State-Wide Scale

The DMS should be able to compile, store and distribute data collected in the mapping campaign and beyond for future work. Often data and models are compiled into models aimed for a specific smaller project area. Although this makes sense in a local ad hoc perspective, learnings are that these models are not maintained over the years and therefore of limited use on a longer term and often redone again, when new knowledge arises. The DMS should therefore aim to be able to compile onto one, or a least a few unified state wide model(s). In order to do so, careful work must be done to set up a basic model and model parameters.

DMS on a Local/GSA level

On a local level, the DMS should be focused on delivering results, rather than the data itself. This means establishing specialized webpages with relevant thematic maps should be in focus, thus excluding the more technical background data, although these should also be accessible if needed. Relevant thematic maps could be isopach maps (aquifer- and aquitard thicknesses), water levels, infiltration areas etc. besides predefined (conceptual) cross sections. A live 3D model would also give the user a more comprehensive of the hydrogeological situation.

Data Uploaded For Use in Developing the  HCM

Many kinds of data will contributing to the development of the HCM: well data with hydraulic properties and water chemistry, topographic maps, geologic maps etc, previous established cross sections and hand drawings, geophysics – airborne, and ground-based – ERT, DC, EM, TEM, seismics, geophysical logs, and existing 3D models that can be used as guide for new models. As these data will be used in the model, they’ll have to be in a format that is possible to work with in a 3D modeling software. Suggested guidelines:

  1. All data must be digital and have qualified 3D coordinates.
  2. A common geographic reference system must be defined, and used, in order minimize problems related to mixed coordinate systems.
  3. Data formats should be of well described standard – like comma separated files, common file formats (e.g. GeoSoft exchange format), or databases of different kinds.
  4. Well data should be stored in an open database format that can be used for updating content querying and quality assessment including a user interface. This should preferably be web based and distributed via web services.

Some geophysical data formats can be complex, and a standard should be defined. In the GAP project a common database format called GERDA is used.

We provide a table listing data that should be collected and included in the DMS in mapping the groundwater systems of an area. Not all these datatypes will be collected in a specific mapping campaign. The acquired data typically varies depending on availability, geological setting, time and budget etc.

Sharing Data

Sharing data between stakeholders is important in order to succeed in developing HCM’s that can establish the foundation for resilient planning. The DMS needs to be able to handle different permissions for different stakeholders/users. Some users will have administrative privileges and be able to upload data, assign access to data and also be able to give permissions to other users and remove them again. The administration scheme should have both permission system on user level, but also on role level for easy administration.