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l. new FIRM in 1986. As an outcome of the significant floodplain boundary changes an updated "Major Drainageway Planning for Boulder Creek Tributaries" prepared by Greenhorne & Q'Mara. Inc, was adopted in 1986. This replaced the Wright-McLaughlin master plans. The Comprehensive Drainage Utility Master Plan (CDUMP) was adopted in January 1989 as part of an identified need to update the floodplain management program. CDUMP defined the scope and timing for necessary capital improvements for floodplain management and also addressed flood hazard mitigation (for high hazard structures acquisition activities), storm water quality (creating the storm water quality program in Utilities), administration and operations, funding, and program implementation. CDUMP was developed concurrently with the Tributary Greenways Master Plan (TGMP) in an effort to integrate program activities. A primary CDUMP goal was to identify and set priorities for flood mitigation construction projects in order to develop the Capital Improvement Program (CIP) and required fmancing. During this same time frame the city developed and adopted the high hazard zone and conveyance zone as part of updated floodplain regulations under Ordinance 5199 on June 27, 1989. The major emphasis of the new regulations was to protect life safety during flooding with a defined high hazard zone that identified those portions of the floodplain where a person could be swept away in flooding. Development of structures intended for human occupancy is prohibited in the high hazard zone. The conveyance zone identifies areas in the floodplain beyond which full encroachment from its edges would raise flood elevations by more than 0.5 feet. Development may not create any increase in flood elevations in the conveyance zone. The term "conveyance zone" was adopted to avoid confusion with the NFIP floodway definition. The NFIP established the Community Rating System (CRS) in 1990 to reward communities doing more than the minimum NFIP requirements to prevent or reduce flood losses. The CRS is intended to provide incentive for communities to adopt higher regulatory standards than NFIP minimums. Under the CRS flood insurance premium rates for the community are adjusted to provide credit for additional community efforts to reduce flood hazards. Non-regulatory activities, such as floodplain acquisition programs, community-outreach and flood education programs, early warning systems and advanced floodplain mapping, also earn credit. The CRS operates under a point system, similar to local fire department ratings used to adjust standard homeowner insurance premiums, and results in a community receiving a certain Class rating. A Class 1 rating would reduce flood insurance premiums by 45 percent while a Class 10 rating receives no reduction. Boulder has been participating in the CRS and currently has a Class 8 rating that provides a 10 percent reduction in local insurance premiums. Boulder has continued to implement the floodplain management policies that were adopted as part of the CDUMP in 1989. The CIP program has continued to implement the 1986 major drainageway master plan along the tributaries, and substantial structural drainageway improvements have been completed along Goose Creek and Bear Canyon Creek to contain 100-year flooding. Acquisition of high hazard properties has also gained importance under the CDUMP. Recent floodplain management activities have included updating several floodplain studies for Bear Canyon Creek, Boulder Creek, Fourmile Canyon Creek, Gregory Creek and Wonderland Creek. Updated master planning efforts have been initiated on Fourmile Canyon Creek and South Boulder Creek following identification that unmapped spills from these two floodplains will inundate numerous developed properties not currently mapped in the 100-year floodplain. Increased public involvement and oversight by an Independent Review Panel have also been added to these master planning updates. 4