The Port of Portland and the City of Portland Bureau of Environmental Services have partnered with the Drainage Districts to revegetate parts of the Colombia Slough’s banks, Native vegetation will enhance wildlife habitat, provide natural water filtration, shade the slough for water quality and create an attractive waterway for all.

Please see “Links” for links to partners.

Corp of Engineers:  Please see new Link "So, You Live Behind a Levee"

Federal Facilities Maintenance Requirements

The Corps sets engineering standards for the design, integrity and maintenance of the federally authorized levees and other flood protection works that make up the infrastructure of the drainage districts (see Appendix B, Federal Flood Protection Maintenance Requirements). The drainage districts are designated as the local sponsor and as such, are responsible for meeting the standards for OMRR&R of the levees, associated drainage structures, and pumping plants. An overview of the infrastructure and the operating and maintenance practices for the drainage districts is provided in the Districts’ Infrastructure and Operating Parameters section of this report.

The Corps annually inspects and assigns a condition code to the drainage districts’ levees and associated flood protection facilities. Since federal funds provided a significant share of the original construction costs, as long as the levees and other structures are maintained to Corps standards, federal funds are usually available for repair following a flood event. If the drainage districts do not properly maintain the flood protection facilities, the Corps would downgrade its evaluation of the flood protection system, and flood insurance rates and development financing would be jeopardized. Without the districts’ systems for flood protection, local development of properties in the floodplain would not be possible. State regulations and local zoning codes would not allow any development to occur that is incompatible with river flooding, and construction financing and flood insurance for local development would not be available.

In 1968, Congress passed the National Flood Insurance Act, which created the National Flood Insurance Program (NFIP), to correct some of the shortcomings of flood relief programs and the high costs of flood protection projects (see Appendix B, National Flood Insurance Program). The NFIP was broadened and modified by the Flood Disaster Protection Act of 1973, which required that buildings in flood hazard areas have flood insurance as a condition of federal aid or loans, and as a condition for receiving federal disaster assistance. There also are “sanctions” for non-participation which make it hard for communities wanting federal assistance to avoid joining the NFIP. Since 1973, the program has been amended several times.

The NFIP is designed so that floodplain management and flood insurance complement and reinforce each other. The FEMA makes flood insurance available provided that adequate floodplain management regulations that mitigate flood risk are implemented. The drainage districts maintain water levels below the BFEs established by FEMA for each district to prevent flooding. Also, by maintaining their infrastructure to Corps standards, the districts assure FEMA of floodplain safety and provide the assurance needed for new development to obtain flood insurance. The Cities of Portland, Gresham, Fairview, Troutdale and Wood Village, as well as Multnomah County (unincorporated areas), are participating communities in the NFIP (Table 2). As shown in the table, Wood Village has no special flood hazard area (all land is classified in zone C, an area of moderate or minimal flooding).

Source: FEMA Community Status Book (January 9, 2002); http://www.fema.gov/fema/csb.htm

A community’s floodplain management program and permit records are reviewed periodically by the Department of Land Conservation and Development (DLCD, the NFIP coordinating agency in Oregon; see Appendix A, Floodplain Management and Flood Hazards). If a community does not uphold its part of the agreement and fails to adequately enforce its floodplain regulations, FEMA has recourse through three approaches: reclassification, probation, or suspension from the program.

An important objective of the NFIP is to protect buildings constructed in floodplains from damage caused by flooding. Flood is defined in the standard flood insurance policy, in part, as a general and temporary condition of partial or complete inundation of normally dry land areas from overflow of inland or tidal waters or from the unusual and rapid accumulation or runoff of surface waters from any source. The NFIP building design and construction requirements apply to new construction and substantial improvements of existing buildings in SFHAs to protect a building from flood-related damages. The SFHAs are based on a flood that has a one percent chance of being equaled or exceeded in any given year (the 100-year flood). A one percent annual chance flood has a 26% chance of occurring over the life of a 30-year mortgage. The NFIP requirements specify that new or substantially improved residential buildings must have the lowest floor (including basement) elevated to or above the BFE in the SFHAs.

The FEMA identifies and maps flood hazard areas in each community by conducting a Flood Insurance Study (FIS) and publishing a Flood Insurance Rate Map (FIRM). The FIRM shows areas within the 100-year flood boundary (A zones or V zones in coastal areas), which is determined from information obtained from the community, from floodplain topographic surveys, and/or from detailed hydrologic and hydraulic analyses. The FEMA works closely with community officials during the preparation of a FIS and FIRM. Areas between the 100-year and 500-year flood boundaries are moderate flood hazard areas. Areas above the 500-year flood level are minimal flood hazard areas (Appendix B, National Flood Insurance Program, contains definitions of flood hazard zones).

Oregon’s program for land use planning includes statewide planning goals that apply to local governments, special districts and state agencies. The goals are mandatory and have been adopted as administrative rules (OAR Chapter 660, Division 15). Oregon’s statewide goals are achieved through local comprehensive planning and zoning codes. State law requires each city and county to have a comprehensive plan, and the zoning and land-division ordinances needed to put the plan into effect. Of particular interest to floodplain management and flood hazards is Planning Goal 7, Areas Subject to Natural Disasters and Hazards, which requires local governments to adopt flood protection policies and controls. (see Appendix A, Floodplain Management and Flood Hazards). State rules associated with Planning Goal 7 require the uniform use of NFIP materials by all local governments.

The flood mitigation programs and strategies in Oregon are primarily the responsibility of the DLCD, the Department of Consumer and Business Services, Building Codes Division (BCD), and the Office of Emergency Management (OEM; see Appendix A, Floodplain Management and Flood Hazards). Every community in Oregon with identified flood hazards is a member of the NFIP, and must adopt the NFIP minimum requirements. The cities and counties subject to flooding have adopted floodplain development codes and ordinances in accordance with Planning Goal 7 and the NFIP, which allows their residents to purchase flood insurance.