About the Conservation Module

UrbanSim has partnered with The Nature Conservancy’s California chapter to offer UrbanCanvas Modeler Parcel Model subscribers in the state of California access to the Conservation Module. The Conservation Module is a natural and agricultural resource accounting module that evaluates the development and density patterns produced in UrbanSim scenarios and quantifies the impacts to natural and agricultural resources. Metrics are calculated for water resources (e.g. reductions in groundwater recharge, impacts to water quality, development within drinking water source watersheds), agriculture (e.g. economic impacts from the loss of cropland), biodiversity and habitat (e.g. development within known conservation priorities, reduction in acres of habitat for threatened and endangered species), and the potential greenhouse gas emissions from loss of carbon stored in the land base. The full list of metrics that the conservation module quantifies and reports can be found here.

Applicable subscribers have tools available in the platform to:

• Apply the conservation module on UrbanSim scenarios

• Upload local conservation priority areas and specific species to customize conservation module metric reporting to local priorities and species of interest

• View base year and scenario end year conservation module metrics and indicators

• Generate scenario comparison charts via the conservation module chart wizard

The use of the conservation module is optional and can be used for any UrbanSim scenario. The conservation module will run at the end of the UrbanSim simulation process and will calculate metrics for the 2010 base year and the simulated end year. For regions on the order of the size of the 9 county San Francisco Bay Area (4.5 million acres), typical module run times can reach up to 1-1.5 hours. Scenarios that use the conservation module will have additional metrics available for download and inspection on the map that pertain to the computed environmental impact of development on parcels that have changed in household and employment unit per acre density. Only parcels that have experienced an increase in density between the base and end year are considered. Densities are categorized into land cover categories for use by the conservation module based on the crosswalk table below here. For each scenario you may download the CSV of region-wide Conservation Module metrics and can add the metrics to the Conservation Module chart wizard to automatically populate charts comparing metrics across scenarios.

Land cover categories and UrbanSim DUA crosswalk

Land cover category	Density Range (Dwelling Units Per Acre (DUA))
Developed, Open Space	0.5-1 DUA
Low Density, Developed	1-1.5 DUA
Medium Density, Developed	>1.5 DUA

Dwelling Units Per Acre (DUA) includes housing units and job units. Job units uses an assumption that each job requires 400 sqft. Land cover categories are based upon the Multi-Resolution Land Characteristics (MRLC) Consortium’s 2011 National Land Cover Database [1]

The conservation module was developed by The Nature Conservancy, American Farmland Trust, Sonoma County Agricultural Preservation and Open Space District, and Calthorpe Analytics with generous support from the S.D. Bechtel Jr. Foundation and the Resources Legacy Fund. The conservation module is currently being maintained by The Nature Conservancy.

Conservation Module Documentation

Detailed documentation on the Conservation Module from The Nature Conservancy can be found here and includes detailed descriptions of each metric.

Nature Conservancy Environmental Constraints for CA

The Nature Conservancy has provided environmental constraint data for CA that can be used to build a scenario that avoids placing development in areas with important natural resources. The data can be downloaded here.

Subscriber Availability

The Conservation Module is currently only available to UrbanCanvas Modeler Parcel Model subscribers in the state of California.

References

[1]

Homer, C.G., Dewitz, J.A., Yang, L., Jin, S., Danielson, P., Xian, G., Coulston, J., Herold, N.D., Wickham, J.D., and Megown, K. 2015. “Completion of the 2011 National Land Cover Database for the conterminous United States-Representing a decade of land cover change information.” Photogrammetric Engineering and Remote Sensing, Vol. 81, No. 5, pp. 345-354.