WARNING: TECHY POST!!!
It's Monday morning so we're working back at Logistics base. I'm working with Shelter team today. Shelter have so far conducted 2 surveys in the field: 1. a cadastral survey containing the location of the building plots and 2. an enumeration survey containing socio-economic information for the whole population of Delmas 19. Both commenced from May 2011 and both are still being finalised. I am waiting for these datasets to be validated then we will integrate the data, start performing some analysis and set up the platform ready for monitoring and evaluation data.
The cadastral survey has been conducted by a local survey team (SAGESS) with little experience of working on this sort of scale. Independent checks in the field reveal that many of the building plot locations are incorrect: some plots are missing, others overlap and sometimes there is more than one owner to each plot. Its not surprising that there are problems with the process due to the density of the slums and the lack of accessibility to many of the plots. In Cite 4 it is almost impossible to distinguish one structure from another due to the high density.
In addition to the practical mapping of building locations, identifying beneficiaries and tracking population movement within the area is also proving to be a massive obstacle to the progress of the reconstruction process - this needs to be done before any planning can take place.
The process of validating the enumeration survey involved a team of volunteers independently visiting the households after the survey to validate the owner of each plot. In Cite Romain for example, there were 128 building plots present in the enumeration database. These entries were validated by comparing the enumeration codes to the cadastral map produced by another team member. There were only 65 matches and 63 mis-matches that had to be verified again in the field. Of the 63 that needed to be verified, 21 names were correct, 31 were eliminated because the people have moved out of the area and 11 still had to be verified.
As a result the team are having to work extraordinarily hard to revisit the site time-and-time again to identify the beneficiaries, pinpoint their location in the cadastral map and then verify this information. This process would have been made much simpler if building plots were created at the very start of the project and the enumeration entries directly linked to the plots then.
To make matters worse there are conversion errors when the CAD map (DWG format) is imported into ArcGIS. When the CAD is being imported the polygons are imported as a combination of lines and polygons and the attributes contained in the CAD (number of storeys, damage level, owner name) is lost, which means this information will need to be added manually to the GIS. I am trying to develop a work-flow with the GIS staff member to minimise the amount of work required when performing this conversion.
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