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<br />CHAPTER 3. MITIGATION PLAN <br /> <br />3.1 Mitigation Goals and Objectives <br /> <br />The overall goal of the mitigation plan is to restore a naturally self-sustaining wetland/riparian <br />ecosystem along the length of the MA that supports the best functional conditions that can be <br />practicably established. The obiectives of the mitigation plan will focus on the six main factors <br />that are affecting functional conditions: <br /> <br />. Maintain adequate streamflow conditions within the MA. <br />. Remove negative effects from livestock grazing. <br />. Reduce proliferation of undesirable weed species and replace with desirable species. <br />. Protect or stabilize eroding streambanks. <br />. Restore degraded floodplain within straildttened and leveed river reaches. <br />. Improve the condition of upland buffers adjoining wetland/riparian habitats. <br /> <br />Reclamation will pursue the mitigation goals and obiectives without hindering Colorado's use of <br />its entitlement under the La Plata River Compact. If in time the MA needs additional water to <br />maintain its functional state, Reclamation will be responsible to find and implement flow <br />augmentation methods, some of which are discussed in this chapter. <br /> <br />3.2 Maintaining Adequate and Sufficient Streamflow Conditions <br /> <br />The La Plata River has .the traits characteristic of both a snowmelt-fed, perennial stream and a <br />flashy, ephemeral stream. The peak runoff period generally occurs in late April to early <br />May, with flows decreasing until low summer flows are reached by July. Approximately 75 <br />percent of the annual flow volume recorded at the Colorado-New Mexico State Line Gauge <br />(Figures 6 and 7) occurs during the months of March through June. Figure 8 shows an <br />approximate average year (1998) annual flows into and out of the La Plata River System. <br /> <br />During most years, large stretches of the La Plata River start going dry by late June, including <br />areas just upstream from the MA. This is due to lower river flows and upstream irrigation <br />diversions. However, during these low flow periods irrigation return flows and ground water <br />springs in the MA produce sufficient water to cause a small perennial flow to occur in the La <br />Plata River through the MA (1 to 2 cfs at the north end (north end of Tract III) of the MA and <br />gaining to approximately 4 cfs at the confluence of Long Hollow). During these low flow <br />periods, Long Hollow adds approximately 4 cfs to the La Plata River. <br /> <br />-17- <br />