Understanding Your Risk and Impacts

 Drought Impact Assessment

An impact assessment highlights sectors, populations, or activities that are vulnerable to drought. Drought impact assessments begin by identifying direct consequences of drought, such as reduced crop yields, livestock losses, and reservoir depletion. These direct outcomes can then be traced to secondary consequences (often social effects), such as the forced sale of household assets or land, dislocation, or physical and emotional stress. This initial assessment identifies drought impacts but does not identify the underlying reasons for these impacts.

Drought is typically associated with a number of potential impacts. For practical purposes, the drought impacts can be classified as economic, environmental, or social, even though several of the impacts may actually span more than one sector. Using an impact checklist is one easy way to help categorize drought impacts that affect your activities.

Impacts should be examined for their relevance in past or recent droughts, but consideration should also be given to the question “What drought impacts will be seen in the future?” This last question is crucial as populations shift and water demands change. The United States sections will help you better understand past and present drought conditions, and future impacts can be estimated through your knowledge of trends over time. Literature reviews and case studies and scenario building can also help examine the range of past and future drought impacts.

Understanding the changing nature of drought impacts is an essential step in the process of reducing drought risk. Once this is done, the next step is to rank the impacts that most affect your activity or livelihood. You can then investigate the underlying causes of the drought impacts and begin the process of identifying and implementing appropriate drought mitigation actions.

Real-World Case Studies – Drought Impact Assessments in New Mexico, Nebraska, and the Hopi Nation (excerpts from Hayes et al., 2004)

New Mexico
In response to severe drought in 1996, New Mexico completed a drought mitigation plan in 1998. To develop a proactive plan that included specific mitigation actions, the state went through the important process of identifying their drought risk. New Mexico roughly followed the methodology suggested by Knutson et al. (1998), adapting the process to the available resources and needs.

To better understand drought impacts within the state, New Mexico organized four impact assessment subgroups representing the sectors most affected by drought in the state, including (1) agriculture, (2) drinking water, (3) wildlife and wildfire protection, and (4) tourism and economic impacts. These subgroups identified the major drought impacts occurring in each sector, although they did not assess temporal trends in impacts that may have helped assess the dynamic nature of vulnerability across the state.

Nebraska
Nebraska first developed a drought plan in 1986. In 1998, efforts began to update and revise the plan, and this process culminated in the Nebraska Drought Mitigation and Response Plan in 2000.

To better understand drought impacts within the state, Nebraska organized impact assessment subcommittees that reflected the sectors most affected by drought: the Agriculture, Natural Resources, and Wildlife Subcommittee and the Municipal Water Supply, Health, and Energy Subcommittee. Through a series of group discussions, the subcommittees identified important impacts. Like New Mexico, no effort was made to look at the temporal trends in drought impact occurrence.

Hopi Nation
The Hopi Nation, located in northeastern Arizona, retained a private consulting group to assist them in developing parts of their tribal drought mitigation plan. The risk analysis portion of the plan followed the methodology suggested by Knutson et al (1998) quite closely (S. Jones, personal communication, September 2001). This information is included in the draft of the Hopi Drought Plan, which was completed in 2000 but is still pending approval by the United States Congress.

Based on a review of the Hopi Reservation’s climate, natural resources, and social characteristics, the four areas that the Hopi considered to be most vulnerable to drought and to experience the greatest impacts were (1) range and livestock, (2) agriculture, (3) village water supplies, and (4) environmental health.

A unique feature of the Hopi Drought Plan is the inclusion of current and proposed monitoring systems to evaluate changing soil, vegetation, and water resources for farming, ranching, and domestic purposes. The drought plan describes establishing a network of approximately 60 transects to provide a detailed analysis of range conditions. The transects will be selected to represent major climates, soils, water resources, and land uses present on the reservation, and will help to identify trends in vegetation health. These monitoring networks will not only help monitor and quantify the effect of drought impacts, but can also be used to assess the effectiveness of any mitigation actions that are implemented.