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. . . Sub-Reach Ratings Existing river condition evaluations were determined by a ranking system which combines technical scoring of decision criteria by the technical experts and weighting of the decision criteria by the T AC. This allows the technical evaluation of each sub-reach to be combined with those attributes in the sub-reach that the T AC values as restoration objectives. A simple weighted average methodology was used for the scoring scheme, whereby alllechnical evaluations are normalized from 0 to 10, with 10 being the highest possible value, and multiplied by the weight given the criteria by the TAC. ES.3.7 Local Planning Issues A review of existing floodplain managemenl and comprehensive land use plans as Ihey relate to the RGHRP objectives was conducted. Emphasis was on floodplain management, zoning and land development regulations that affect potential developmenl in Ihe river corridor. ES.3.6 The five criteria were based on the original stated project objectives. Because the channel capacity and Compact delivery objectives are not mutually exclusive, these two project objectives were combined into a single decision criterion. In addition, because channel stability was nol originally stated as a project objective but is an underlying necessity of any river restoration project, it was added as a decision criterion. The technical team then assigned scores to each of the decision criteria through several technical evaluation measures. The criteria and evaluation measures are shown in Table ES-4. Floodplain management is a tool available to local communities to assure that development in flood-prone areas meets minimum public safety standards and is consistent with local land use objectives. Locally adopted floodplain management regulations currently allow governmental bodies in the Rio Grande corridor to exercise a certain amount of control over the nature of development in the floodplain areas in the corridor. All of the entities along the Rio Grande within the study reach currently have floodplain ordinances that include requirements for floodproofing or setting finished floor elevalions at or above the base (I DO-year) flood elevation, and establish limitations on increases in the base flood elevation within the floodway. However, patterns of recent development indicate that these regulations are not uniformly or aggressively enforced in all areas. In addition, new structures and access roads in floodplains have been elevaled on fill (consistent with floodplain regulations) for protection, but have in turn caused flooding problems in upstream areas by blocking flows in the floodplain. Criteria Evaluation Measures Channel capacity and delivery of Compact flows Probability of bank-full exceedence Impacts on structures from deliverv of comoact flows Protection from flood damage Structural damage from flood flows Protection of personal safety during flood flows Adequacy of existing floodplain regulations Areas of special consideration Maintenance of riparian habitat Vegetation density Regeneration of riparian vegetation Human activity in riparian areas Agricultural disturbance of riparian areas Terrestrial wildlife habitat Aauatic habitat Access to river for water diversion River stability at diversion Avulsion tendency Cutoff tendency Ability to divert decreed capacity Debris problems Sedimentation at structure Existing maintenance problems Diversion access to river Planform location Adeouacv of desian Channel stability Bank stability Meander miaration Tabla ES-4. Decision Criteria and Technical Evaluation Measures Comprehensive land use plans are or could be used by communities in the Rio Grande corridor to affect the nature and location of land use impacts on the river system. This can be done by precluding or encouraging certain types of land uses in selected areas through zoning designations, establishing special development standards to be applied to sensitive river corridor areas, and establishing special development standards to be applied to sensitive river corridor areas. None of the land use planning documents and ordinances currently being used by entities in the Rio Grande corridor provide adequate ability to protect and preserve the corridor from adverse impacts of future land development. All entities have adopted floodplain some are slricler than others. Floodplain regulations guide but do not prohibit development in the Rio Grande floodplain. Floodplain regulations have not been uniformly or aggressively enforced in the past. Some solutions to floodplain development meet the requirements of the regulations but cause other problems (e.g. placing access roads on fill). Comprehensive land use planning practices vary significanl1y among the entities in the study area. Development pressure in the river corridor is greatest in Soulh Fork and the unincorporated areas near South Fork, Del Norte and Alamosa. None of the land use planning documents and ordinances currently being used by entities in the Rio Grande corridor provide adequate ability to protect and preserve the corridor from adverse impacts of future land development. in the Rio Grande but standards, The following local planning issues are important to understanding existing conditions corridor and developing solutions to deal with existing problems. minimum FEMA mee that regulations . . . . Weighting of each criterion allowed the TAC to provide input on both the evaluation of existing reaches and the recommended alternatives for restoration. During the TAC meeting on February 16,2001, an exercise was undertaken with the T AC to determine the importance of the criteria for each sub-reach. During the T AC meeting, each main reach within the study area was discussed separately. The relative importance of each criterion for each sub-reach is presented in Table ES-S. 6 ES- . . . ES-15