Land Use Workgroup
Scope and Purpose
Land use is one of the most critical data sets for the Chesapeake Bay Program (CBP) Watershed Model. Land use data have previously been prepared by the CBP Land Data Team in consultation with the CBP Watershed Modeling Team. Land use classifications have been driven by available data and by the expressed needs of CBP workgroups to inform management decisions. The work of the Land Data Team has been reviewed by CBP Scientific and Technical Advisory Committee (STAC) in 2008 and 2010. During the Watershed Implementation Plan (WIP) process, differences have come to light between the land use data set used by that CBP that covers the entire watershed over a multi-decadal period and local-scale information. These differences have caused difficulties in implementation planning and reporting in support of the WIPs. As the responsibility to implement restoration efforts is pushed to the local governments, it is vital that the land use data used in the watershed model is perceived as relevant at the local government scale. To this end, the Land Use Workgroup will directly involve stakeholders in the generation of land use data for modeling. The challenge will be to assemble a more accurate baseline dataset using local information to the extent possible while estimating historic land use acreages in a clear, transparent, and logical fashion.
Goals include:
- To create a temporally, spatially, and categorically consistent and accurate land use dataset from 1982 to 2012 for all jurisdictions in the Chesapeake Bay watershed using the best available data at all scales.
- To approve methods for projecting future land use conditions for all jurisdictions in the Chesapeake Bay watershed.
Projects and Resources
Review of Draft Current Zoning 2025 Land Use Forecast
On November 8th, the LUWG agreed to exclude ultra-rural areas from near-term 2025 development. That change has been made to the attached resulting in slightly more development overall, less farmland, fewer septics, and more forest compared to the version distributed last week. The changes are generally very minimal- less than 1% at the LRSEG scale. Please review the attached “Current Zoning” future land use scenario for the year 2025. Please email comments directly to Peter Claggett (pclagget@chesapeakebay.net) and copy Lindsey Gordon (Gordon.Lindsey@epa.gov) by December 8th, 2017. We appreciate receiving comments as soon as is convenient.
Please note that these data are all products of the Chesapeake Bay Land Change Model’s (CBLCM v3a) forecasts and backcasts and therefore do not incorporate construction acres, the Census of Agriculture, nor the extrapolation of Census of Agriculture trends which are all incorporated into the Phase 6 land use data via a “true-up” process conducted by the CBP modeling team and which we’ve discussed during previous meetings. Therefore, the attached data are not the exact data informing the Phase 6 watershed model but they do dominantly influence the Phase 6 land uses and they are the exact data produced from the CBLCM for which the LUWG has technical oversight responsibility.
In addition to the data described below, USGS has posted a composite of a single urban land use iteration for the year 2025 (e.g., one of 101 Monte Carlo simulations depicting future residential, commercial, and mixed use development at 30m-resolution) on the Chesapeake Bay Phase 6 Land Use Viewer (https://chesapeake.usgs.gov/phase6/map/ ). All of the 101 simulations exhibit similar patterns of growth at the county level; only the exact locations of new development and the overall magnitude of new development differ among iterations. The Phase 6 Viewer is readable in Internet Explorer or Google Chrome (preferred). If you encounter difficulty accessing the site, refresh the webpage (<CTRL> F5). In the Viewer, you’ll see a “Phase 6 Future Land Use” menu (lower right) that includes maps of “Residential Suitability” and “Commercial Suitability”. These maps display undeveloped lands that are judged suitable for future development based on zoning, slope, and protection status. They also provide a quick means of evaluating which counties provided usable zoning information (e.g., those counties with limited land available for development). For jurisdictions within the Washington Metro COG region, Traffic Analysis Zones (TAZ) projected to accommodate <= 10 new housing units or jobs over the period 2015-2045 were excluded from near-term growth in 2025. Moreover, the proportion of future development accommodated via infill/redevelopment within COG jurisdictions was calculated as the maximum of either the CBLCM infill estimates or an infill estimate based on the proportion of TAZ-level forecasted growth which cannot be accommodated as greenfield development because it exceeds current development capacities at the TAZ scale.
- Current zoning acronym key (10.22 KB) A description of acronyms used in other attachments. (Corrected 11/15/17)
- CNTY_Sewer_Septic.csv (32.88 KB) County-level trends in population on sewer and septic and the number of septic systems, 1984 – 2025.
- P6LU_CNTY_Trends_v13.xlsx (187.34 KB) Full-county land use trends from 1984 – 2025 for all counties within, straddling, and adjacent to the Bay watershed.
- P6LU_ST_Trends_v13.xlsx (32.44 KB) State-level trends in overall development, farmland, and natural lands from 1984 -2025 for full counties within, straddling, and adjacent to the Bay watershed.
- County_infill_taz.xlsx (20.59 KB) The proportion of forecasted residential and commercial development that is expected to be accommodated through infill and redevelopment (i.e., not contributing to the conversion of forests or farmland).
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Current Zoning Review Expectations (515.62 KB)
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2025 Forecast Development Timeline (499.82 KB)
- Cnty rank dev13 25.csv (5.82 KB) Ranking of counties by those projected to experience the most development over the coming decade
- Current Zoning Announcement Email Text (15.83 KB)
2025 Land Use Forecast Scenarios
Here you will find a repository of information related to the CBP effort to simulate 2025 land use conditions through various scenarios. Contact either Lindsey Gordon (gordon.lindsey@epa.gov) or Peter Claggett (pclagget@chesapeakebay.net) with questions.
- Chesapeake Bay Land Change Model Outputs Key (9.18 KB)
- 2025 Draft Current Zoning Results by County (21.4 KB)
- 2025 Draft Current Zoning Results by LRSEG (142.25 KB)
- 2025 Draft Current Zoning Results by State (1.13 KB)
Phase 6 Land Use Review
The Chesapeake Bay Program (CBP) Partnership is in the process of improving and refining the Phase 6 suite of models used to inform actions needed to restore the Chesapeake Bay and to meet the requirements of the Bay Total Maximum Daily Load (TMDL) pollution limits. Over the past 3 years, the CBP Partnership has collected land use, parcel, impervious surface planimetric, and other data from local governments to improve its characterization of the landscape. By combining these local land use datasets with the high-resolution land cover currently being produced, the CBP is able to create a hybrid 10-meter resolution land use/land cover raster database ("Phase 6 Land Use Database") composed of 13 distinct land use/cover datasets, all of which have unique nutrient and sediment loading characteristics.
Following production of the Phase 6 Land Use Database, all local jurisdictions will be asked to review the Phase 6 Land Uses and overlay data to help identify errors in the mapping of turf grass, agriculture, open space, water, wetlands, roads, sewer service areas, MS4 (Municipal Separate Storm Sewer System), and CSO (Combined Sewer Overflow) boundaries.
The U.S. Geological Survey has developed a website to facilitate the review and dissemination of the Phase 6 Land Use Database; the website works best using Google Chrome and can be accessed at: http://chesapeake.usgs.gov/phase6/
Here, you will find relevant materials and resources for the Phase 6 Land Use Review.
These materials can also be found on the calendar event page for the Phase 6 Review webinar, which took place on January 19th. A link to this site is: http://www.chesapeakebay.net/calendar/event/23454
A supplemental webinar to provide an update on the status of the Land Use Database development was held on September 20th. A recording of the webinar can be viewed by clicking here. Additional information from this webinar is available on the calendar event page: http://www.chesapeakebay.net/calendar/event/24320/
Additional materials are forthcoming, and include:
1. Frequently Asked Questions (FAQ) Document
2. Review Timeline Schedule
3. Local Data Inventory
4. LiDAR Coverage Map
A recording of the presentation on the Phase 6 Land Cover Data by Cassandra Pallai, Chesapeake Conservancy, can be accessed using the following link: https://epawebconferencing.acms.com/p1fr82q9b69/
A recording of the presentation on the Phase 6 Land Use Data by Peter Claggett, USGS, can be accessed using the following link:
https://epawebconferencing.acms.com/p6xjtqj4se9/
If you would like to be notified of additional updates regarding the CBP Phase 6 Land Use Database, please contact Lindsey Gordon (gordon.lindsey@epa.gov).
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Phase 6 Land Use Review Overview (543.46 KB) Overview of the Phase 6 Land Use Review process, detailing the who, what, where, why, when, and how of the process.
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Frequently Asked Questions (FAQ) (537.82 KB) A summary of frequently asked questions regarding the production and review of the Phase 6 land cover/land use datasets.
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Chesapeake Conservancy Land Cover Production: Presentation (8.14 MB) Presentation from the Chesapeake Conservancy on their production of Land Cover Data.
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CBP Phase 6 Land Use Presentation (9/20/16) (40.05 MB) Presentation from the September 20th webinar on the Phase 6 Land Use Database.
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CBP Land Cover/Use: Presentation (13.44 MB) Presentation from Peter Claggett, USGS, on how the CBP Partnership is developing the Phase 6 Land Use Dataset.
Publications
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Land Use Methods and Metrics Pre-QPM Narrative Analysis 2021
Land Use Methods and Metrics Pre-QPM Narrative Analysis 2021
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Land Use Methods and Metrics QPM Presentation 2021
Land Use Methods and Metrics QPM Presentation 2021
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WQGIT Governance Protocols