Prioritizing Stream Barrier Removal to Maximize Connected Aquatic Habitat and Minimize Water Scarcity

Instream barriers, such as dams, culverts, and diversions, alter hydrologic processes and aquatic habitat. Removing uneconomical and aging instream barriers is increasingly used for river restoration. Historically, selection of barrier removal projects used score‐and‐rank techniques, ignoring cumulative change and the spatial structure of stream networks. Likewise, most water supply models prioritize either human water uses or aquatic habitat, failing to incorporate both human and environmental water use benefits. Here, a dual‐objective optimization model identifies barriers to remove that maximize connected aquatic habitat and minimize water scarcity. Aquatic habitat is measured using monthly average streamflow, temperature, channel gradient, and geomorphic condition as indicators of aquatic habitat suitability. Water scarcity costs are minimized using economic penalty functions while a budget constraint specifies the money available to remove barriers. We demonstrate the approach using a case study in Utah\u27s Weber Basin to prioritize removal of instream barriers for Bonneville cutthroat trout, while maintaining human water uses. Removing 54 instream barriers reconnects about 160 km of quality‐weighted habitat and costs approximately US$10 M. After this point, the cost‐effectiveness of removing barriers to connect river habitat decreases. The modeling approach expands barrier removal optimization methods by explicitly including both economic and environmental water uses

Water conservation master plan.

This is Salt Lake City's latest water conservation master plan (2004). Utah law mandates the City file a plan every five years

Apparent Losses Caused by Water Meter Inaccuracies at Ultralow Flows

Although meter accuracy has been addressed in the past as a potential cause of apparent water loss, the lack of significant data on meter accuracy at low flows has caused losses at these flow rates to be largely ignored. This article provides average low-flow accuracies of different meter types and outlines two methods for estimating apparent losses caused by meter inaccuracy at low flows. By estimating apparent losses and resulting decreases in revenues, utilities can gain a better understanding of the real consequences of meter inaccuracy at low flow rates. Stopping nonrevenue water loss attributable to meter inaccuracy can result in substantial short-term increases in utility revenue. Furthermore, meters that accurately record water across the entire range of flow rates lead to more equitable customer billing. In light of these benefits as well as increased system efficiency, utilities may want to make low-flow accuracy a key consideration in selecting meters for initial installation or replacement