Common use of Providing a Net Conservation Benefit Clause in Contracts

Providing a Net Conservation Benefit. The Service has determined that the conservation measures, as described above, are reasonably likely to provide a net conservation benefit for the covered species. As described in more detail below, that net conservation benefit will likely occur as soon as the minimum flows provided for in section 4.1 are implemented in the enrolled portions of Chewacla Creek. The conservation measures described above are expected to increase the quality and quantity of habitat available to the covered species. As documented above, lack of flow is a primary cause of habitat degradation within the enrolled properties. The provisions for minimum flows below Lake ▇▇▇▇▇▇▇▇ Dam, the monitoring of habitat conditions, and the control of subsidence features are expected to ameliorate this situation. The Agreement will provide a stream flow that approximates the normal flows in all reaches of the Creek by adding a portion of the Quarry water to Lake ▇▇▇▇▇▇▇▇ and requiring minimum flow below the dam. For example, based on data from 1980 to the present, Lake ▇▇▇▇▇▇▇▇ has not discharged a continuous flow to Chewacla Creek, as documented by data reported at ▇▇▇▇ (2001) Appendix E-3. Since Chewacla Creek is a “gaining stream” in this section, a requirement for 2.0 MGD at the base of Lake ▇▇▇▇▇▇▇▇ Dam will likely result in more than 2.0 MGD in-stream flow downstream near Pretty Hole during normal conditions For example, ▇▇▇▇▇▇ (2001) reported data for May 2001 demonstrating that when the flow just below the dam was 2.01 MGD, the flow just above Pretty Hole was 4.87 MGD; and, later that month, when the flow below the dam was only 0.57 MGD, the flow just above Pretty Hole was 1.39 MGD. With the control of subsidence features provided for in the conservation measures, the 2.0 MGD requirement below Lake ▇▇▇▇▇▇▇▇ should provide more natural flows in Chewacla Creek within the enrolled properties. Subsidence feature control, coupled with the minimum flow requirement at Lake ▇▇▇▇▇▇▇▇ Dam, is expected to restore year-round flow to that section of Chewacla Creek between Pretty Hole and outfall 2 that has been dewatered. This section, because of its present intermittent nature, is not available habitat for the covered species. With implementation of the conservation measures, that section is expected to become fully available for repopulation by the covered species. Moreover, year-round flow in that section is expected to increase the opportunity for host fish to access the covered species. The presence of likely host fish (largemouth bass) has been documented upstream of Pretty Hole (▇▇▇▇▇▇▇▇▇▇ 2001), and the ability of fish to travel through the intermittent section has been documented (▇▇▇▇▇▇▇▇ 2001). Under the conservation measures, year-round fish migration and increased interaction between the covered species and host fish will be possible. Increased fish migration from downstream of the intermittent section will also make it more likely that southern clubshell, Pleurobema decisum, and ovate clubshell, Pleurobema perovatum, will repopulate these sections. Known populations of these two covered species occur in Chewacla Creek downstream of the enrolled properties (USFWS 2000). Mussel reproduction involves the development of larval forms known as glochidia from fertilized eggs (USFWS 2000). These glochidia attach to the gills of certain host fish as parasites, remaining there for a period ranging from a week to several months (USFWS 2000). After this parasitic period, the glochidia develop into juveniles and detach from the host fish (USFWS 2000). Thus, host fish provide a mechanism for transporting mussel juveniles over a wide range (USFWS 2000). Providing year-round flow to sections of the enrolled properties that have been dewatered will allow host fish to transport glochidia from the downstream existing populations of the covered species to the upstream areas of the enrolled properties now largely disconnected, thereby enabling those covered species to repopulate those areas of the enrolled properties. The overall expected result of the conservation measures is a more natural flow in all sections of Chewacla Creek and an overall increase in the habitat available to the covered species.