Risk Analysis of Cultural Resource within Floodplains of Snoqualmie Valley Presented By Odra Cárdenas Shweta Bhatia Gupta
The Project The impacts of flooding in King County are far ranging and pose significant threats to public safety and regional economic viability, but it also threatens the continuity of cultural resources due to the devastating effects. The cultural heritage along the fertile Snoqualmie river valley comprise quarter of the entire county is subjected to frequent and devastating floods as recently as in year 2006 seasonal flooding.
King County Historic preservation program has recently launched major rural preservation and the project, is a pilot for developing a model of integrated data base for a countywide assessment of historic properties leading to a management plan that will provide a more comprehensive means of treating the county’s significant historic properties during natural disasters . Sponsored By The Project
Enrich the inventory (Data sets) of the cultural resource within unincorporated King
County area of Snoqualmie floodplains.
Explore other datasets that may correlate with the mapped data.
Correlate data sets and map the outfalls.
Provide risk analysis matrix and create models to analyze risk exposure from natural
hazards for heritage properties.
Create an integrated database.
Phase II objectives:
Manipulate data so that it can be used in future modeling applications and analysis;
Mapping information about risk levels for each property.
Formulate hypotheses regarding effects of the mapped outfalls;
Provide report on approach and outcome of analysis.
Research Resource identification Data Gathering Defining dataset Data accumulation Actual project plan Work breakdown structure Task Division Monitoring the process Status reports Work quality Time schedule Management Focus of today’s Presentation Methodology Definition Of Matrix Database design Creating feature set Digitization Reclassification Analysis Process Model Building Reporting
Data Base 1 Flood Data Set Flood Plain Flood Way Water Bodies Contour Data 5ft Contour 2ft Contour Contour TIN Contour _ Merge Historic Site Point Historic Site Structure Parcel KC Zoning Admin Data Models Flood Plain Raster General Analysis Parcel Analysis Modelwoflood Analysis Structure Analysis Result Raster Set Parcel Flood Parcel Soil Parcel Slope Flood Plain uni Soil 15 Slope Flood pl reclass Soil reclass Slope reclass Final Result Zone st –Par Zonal St- Min Zonal St- Mean Project Scope
Digitization 2 A polygon shapefile replaced the existing point shapefile indicating the historic site, but not individual structure within the site. The fields were decided on the bases of inventory documents provided for each site. Point Feature Polygon Feature Project Scope
Matrix 3 Structural Risk Percentage Breakup 40% ,5% Status Architectural Style 20% Structural system And Material 20% Structural Condition 15% Site Condition Foundation Type 40% Cladding Type 20% Roof Type 20% Roof Material 20% Accessibility 30% Extant 30% Change in Use 40% Project Scope
Matrix 3 The Matrix was prepared based on the consequence and likelihood for each contributor, i.e. structural material (20%), This in turn provided a ranking defining the score of each sub-set i.e. foundation and cladding material . Project Scope Structural Material and Construction Type 20 % Contribute Ranking Score Foundation Type (50%) Conc. Poured 1 10 Post & Pier 2 20 Conc. Block 3 30 Log 4 40 Stone 5 50 Cladding(30%) Stucco 1 6 Brick, Stone 2 12 Log, Hr.Wood siding, Rustic drop,Wood Shingles 3 18 Board and Batten, Vertical Board, Asbestos/Asphalt 4 24 Vinyl/Aluminium Siding,Metal 5 30
Model developed by the US Corps of Engineers Hydrologic Engineering Center (HEC) River Analysis Systems (RAS) TIN Flood elevation Detailed survey information Use of HEC RAS Replicate information to verify data HEC1 Flood information HEC RAS
HEC GeoRAS ( extension for ArcMap ) HEC2 Flood information Geo RAS
John and Joyce Place HRI # 0937 Results Maps 5
Risk Impact Prob. Mitigation Contingency Field population must be done manually and is time consuming High Low Distribute the work between members. Reduce study area. It is necessary to digitize polygons of the historic resources since they are currently in point form. To digitize we need reliable aerial photographs. High Low Contact different resources to get aerial photographs. Use the point dataset or parcel dataset, but the results will be less accurate. The results might not be significant Low High Try to include a variety of historical resources. Talk to sponsor on the probability of this risk (the importance of the project resides on the methodology and model, not so much on the results) The sponsor shows little interest in the project. Low High Constant communication with the sponsor. The team will look for other sources of information aside the sponsor and will make own decisions on the project. Not finishing on time the phases of the critical path Very High Low Use Microsoft Project. Leave slack on the programmed activities. Reduce study area. Risk And Challenges