Potential Water Risks Story Map

This map tour investigates possible risks to water resources within Pennsylvania by identifying several variables that can affect water quantity and water quality. The AppStudio interface allows users to (1) interact with these water maps, (2) understand environmental impacts, and (3) pinpoint location specific areas influenced by individual variables.

Since 2009, water quality has become a central issue in conversations concerning Marcellus Shale development. This project investigates the broader context of water risks. Development, industry, and even natural geomorphic elements have the potential to stress on hydrological and sensitive ecological systems. In an effort to quantify potential water risks, a physical spatial model was developed using ArcGIS ModelBuilder. The theoretical underpinnings for the model emphasizes current location-based data with regional variables to determine the most probable distribution of the given phenomenon. Through a qualitative lens, water risks were evaluated and assigned values depending upon their direct and indirect impact to the landscape.

The objective of the “Potential Water Risks” model is to rapidly assess risk on a landscape scale. In order to estimate risk, several anthropogenic and environmental variables were used. Indirect environmental factors, direct environmental factors, development, and industry composed the primary classification framework. Further subsets of these categories were determined and given different value systems based on their relevance to water quality and water quantity. For example, erosion is a major factor that influences stream quality, specifically water turbidity, water temperature, and local flora and fauna abundance.  Soil erodibility, a casual component and direct environmental variable, plays an essential role in determining the health of a stream and is therefore a variable considered within the model. Soil erodibility values were calculated using the k-factor of soil types, classifying soils into low, medium, and high given soil texture and composition.  A total of 18 variables were assessed and given values. To reduce bias from data where locations were not exact, a small watersheds scale was used to minimize concentrated values.

Overall, the model offers a creative spatial framework that analytically calculates areas within the landscape that are potentially at risk for water pollution. By determining areas most at risk, the model provides guidance to communities, organizations and agencies involved in planning and development. Through its application, this model can highlight regions of great water risk and assist in ascertaining most appropriate locations for anthropogenic activity to congregate.

Currently, the Potential Water Risks storymap, available through Marcellus by Design, uses the spatial framework mentioned above for Tioga County, Pennsylvania. The storymap moves the viewer through a sequence of locations that were deemed at higher risk for that particular variable being discussed. Ultimately, this storymap depicts quantitative data in an illustrative way (with the use of photographs of water risks in the landscape).

Process

  • Identify variables that were pertinent to understanding risks to water
  • Examine, organize, and create divisions for potential water risks (i.e. Development Variables, Industry Variables, Indirect Environmental variables, and Direct Environmental Variables)
  • Evaluate potential water risks at the county scale (using small watersheds as the basic unit for calculations)
    1. Tioga County, Pennsylvania was the first test trial: Both a qualitative and quantitative analysis was completed once initial variable values were calculated, differentiating unique weighting systems for individual and group variables.
    2. Potter County, Pennsylvania was used as a second test trial as well as a benchmark to understand variable values in a different landscape context. Minor alterations were made to calculations, methods, and variables previously used in the Tioga County Model.
  • Create a standard Potential Water Risks Model and necessary toolsets using ModelBuilder in ArcMap
    1. Due to the large size of the shapefiles and number of commands needed, a model was created for each of the four variable divisions mentioned above. A final model was then produced that combined the final features of each of those variable divisions.
  • Use the five models and toolsets made to evaluate potential water risks for the entire state of Pennsylvania

Updates

The potential water risk results for all of Pennsylvania has been calculated. We must now examine and analyze this material to further understand the anthropogenic and environmental processes at play. Once the evaluation has been finalized (examined for errors or inconsistencies), a storymap will be developed and made available to the general public.

 

water app