DRB2070 Version 2 represents a revised baseline and two alternative forecasts of urban land cover in the Delaware River Basin (DRB) out to the year 2070. To develop these forecasts, we calibrated the SLEUTH urban growth model for our modeling subregions over the 2001-2006 time period, and validated the model for the 2006-2011 time period. Our collaborators at the USGS modeled land cover to 2070 using the Chesapeake Bay Land Change Model. A comparison of these two products will soon be available to review.
All three scenarios assume 6 feet (2 meters) global average of sea level rise and Category 2 storm surge risk, with moderate repulsion of growth in these areas. For detailed information on the assumptions for each scenario, review our DRB2070 Version 2 Documentation. Our three land cover scenarios include:
- “Baseline” scenario (revised). Represents recent trends in the Delaware River Basin for population growth, employment, regional build-out, regional infrastructure, and conservation efforts.
- “Corridors” scenario: Climate-induced westward expansion: the new frontier (sprawling population growth along corridors). Explores a future with higher than baseline population projections and increased growth along corridors.
- “Centers” scenario: Amenity driven development in urban centers (concentrated population growth in historic centers). Explores a future with higher than baseline conservation efforts and increased growth in existing historic centers.
The primary input layer to SLEUTH is the exclusion/attraction layer, a layer that describes areas that are more or less suitable for urban development. The exclusion/attraction layers used for the baseline, corridors, and centers scenarios are shown below.
View of the exclusion/attraction layer for Quakertown, PA in the baseline scenario
Corridors exclusion/attraction layer used to drive the 2030 and 2070 forecasts
View of the exclusion/attraction layer for Quakertown, PA in the Corridors scenario
For the baseline and alternative scenarios, trajectories were determined for population growth, regional build-out, regional infrastructure, and conservation efforts. These factors, along with assumptions regarding sea level rise and storm surge, were used to develop individualized exclusion/attraction layers prior to modeling future land cover using SLEUTH.
The Pinchot Institute for Conservation sponsored a customized model for the Poconos-Kittatinny Cluster (PKC), one of eight project areas in the Delaware River Watershed Initiative. The PKC region is unique in that the main drivers of land use change are related to the scenic and recreational resources (i.e. second-home development); population and employment growth in distant metro areas; and broader scale economic trends – drivers that were not adequately captured in the Basin-wide model. Given the more detailed modeling approach and the fact that the PKC scenarios are analogous to the Basin-wide scenarios, PKC2070 version 2.1 data within the PKC boundary has replaced the Basin-wide results.
Our three scenarios will be incorporated into the Academy of Natural Science’s Stream Reach Assessment Tool and potentially in Stroud Water Research Center’s WikiWatershed. In the meantime, we have developed an online application for users to easily explore the data (see example image below). Visit our products page to download the data or let us know how you anticipate using our mapping and modeling products in your work!