Verification Datasets of Irrigation Status of Agricultural Lands in Select Areas of Montana, 2019 and 2020

Objectives:

• Provide verified spatial datasets of the irrigation status (irrigated or non-irrigated) agricultural lands throughout areas of interest (example by watershed) on a revolving basis. Datasets are not intended to be extensive datasets of the irrigation status of all agricultural lands in an area, but rather a sample set of verified conditions (examples: irrigated or not, system type, crop type) to be incorporated in models developed to produce annual national maps of irrigated lands. A list of priority areas to be mapped will be developed by both the WY-MT WSC and the Montana Department of Natural Resources and Conservation (MTDNRC).

• Create a shapefile of irrigation status of agricultural lands (by individual fields) of selected areas including attributes such as irrigated/non-irrigated, crop type, irrigation system type, water conveyance system, and water source (groundwater or surface water) being used for the current growing season.

• Develop standardized field data-collection methodology and data processing guidance that can be used nationally within the USGS.

Benefits:

Sources/Usage: Public Domain. View Media Details

• Methodology and data collection efforts could be expanded to include area-wide assessments. For example, rather than just surveying a subset of fields in an area, an entire county or watershed could be mapped to meet project or cooperator needs.
• On-site field visits promote increased understanding of the complexities and variability of agricultural irrigation. It is important for scientists and water-resource managers to physically observe actual delivery (examples: pipelines, ditches, etc.) and application systems (examples: variations in flood and sprinkler systems) as well as the processes that occur during irrigation such as excess watering and run-off.
• Verification/ground truth datasets for models and remote sensing are in tremendous need both locally and nationally.
• Scientists from several USGS WSCs have expressed interest in conducting field-verification projects in their states. Similar efforts could be conducted concurrently within several states allowing for collaboration to develop consistent methodology and nomenclature throughout the nation.

Products:

• A series of digitized, field-verified maps (in a pdf and GIS shapefile) and summary tables (in spreadsheets or as attribute tables) representing a time-series of 2 to 6 observations over the course of 2 growing seasons within each of the selected areas recording the irrigation status of the assessed fields as well as observed crop type, irrigation system type, conveyance type, and source of irrigation water for the period between June 2019 and September 2020 will be generated. All data and files will be released through an USGS data release and will be considered the final product for deliverable. The GIS shapefile, metadata, and tabular data will be accessible on the USGS ScienceBase-Catalog web site. All maps, tables, and shapefile will be reviewed and approved by the USGS before being released. 
• A guidance document describing methodology for the field and map development, data sources, field verification, crop delineation, digitizing, acreage limitations, assumptions, details on selected crops, and idle or vacant lands will be generated. This document is envisioned to support other WSCs to consistently and expediently complete similar efforts in other areas of the nation for future years.