National Drought and Water Availability

Authorized Officers are responsible for determining if and how drought and water availability issues need to be addressed when authorizing public land uses; developing land use and implementation-level plans; developing mitigation strategies; and identifying best management practices. BLM Offices should identify opportunities to improve drought severity and water availability assessments, reduce consumptive water use in times of severe drought, modify authorized uses when necessary, and implement proactive drought resilience measures. Examples of proactive measures include restoring riverscape connectivity, quantifying instream flow needs, inventorying important springs and waterholes, vegetation treatments, and tracking consumptive water use on BLM-administered lands.

To determine if drought and water availability need to be addressed, authorized officers should use an interdisciplinary team or another interdisciplinary approach to assess (1) drought severity and (2) water availability using a landscape-level approach³ for the proposed project or plan on BLM-administered surface lands. The authorized officer should maintain a record of all assessments for the project or plan. The level of staff effort required to complete the initial assessments should not be greater than needed to inform the initial decisions. The level of detail and rigor of the assessments of impacts to inform management decision should be commensurate with the potential impacts, costs, scientific complexities, uncertainties, risks, and other sensitivities associated with the planning or decision-making effort. Drought and Water Availability Impact Assessment Guidelines are available in Attachment 1 to support the assessment of impacts once the authorized officer determines that drought and water availability need to be addressed as part of decision-making.

Assessing Drought Severity: Authorized officers should use the U.S. Drought Monitor (USDM) as the broadest level drought indicator to evaluate drought conditions for the current week, three months prior, and one year prior to the assessment. The BLM should address drought as an issue if the USDM drought category is severe to exceptional (D2 to D4) during any one of these time periods.

While the USDM is an informative composite indicator of drought conditions, no single indicator or index can account for and be applied to all geographic areas and activities. Therefore, offices should compare multiple drought indicators associated with water availability to evaluate drought severity at the relevant landscape scale (e.g., World Meteorological Organization 2016). Drought indicators include precipitation, temperature, streamflow, groundwater and reservoir levels, soil moisture, snowpack, and remote sensing data. Refer to the U.S. Drought Portal for commonly used indicators and indices (numerical representations of drought severity) that can be used to inform drought severity assessments.

Assessing Water Availability: The availability of water for public land management purposes is influenced by water quantity and quality, the timing of water delivery, and human and ecological uses of water. It is existing BLM policy that all land use plans address the availability of water to support the BLM’s mission and programs (refer to MS-7250, Water Rights, Chapter 1.5, Policy, rel. 7-110). This IM extends that policy to implementation-level decisions for activities that require water use regardless of current drought conditions. Water availability assessments should evaluate the potential for the proposed action to affect or be affected by the availability of water for public land management. At a minimum, water availability assessments should document:

• Policies, designations, or declarations issued by Federal, Tribal, State, and local water management agencies in response to drought and water shortages.
• Existing consumptive and non-consumptive uses of surface water and groundwater and points of diversion on BLM-administered lands at the relevant landscape scale.
• The reasonably foreseeable water needs on BLM-administered land in the assessment area.
• Water use requirements for proposed actions.

The assessments identified in this IM will help the BLM to better assess the potential for a proposed action to build or reduce the drought resiliency of public lands and the impacts of drought on humans and ecosystems. This policy leverages the BLM’s interdisciplinary team approach and established agency processes to address the urgency and complexity of rapidly changing environmental conditions.