FHIT

Introduction

Installing monitoring devices at every bridge, road crossing, or other feature of interest is not feasible or cost-effective. Therefore, the flood hazard inventory tool (FHIT) layer applies point data to features within an area, usually a basin.

Data Source

Synthetic Mean Areal Precipitation (MAP) stations are defined using a weighted average of actual precipitation stations in the area. Those stations actually located in the basin are more heavily weighted than a few that may be selected slightly outside the basin.

Strategy

Synthetic stations of data type FhitNovaScoreMax, retrieved from the NovaStar database using Data Web services, are defined to represent the highest NovaScore of the rain stations in an area. In addition, a secondary file contains features and their locations while a third file defines basins. A correlation is made between all features in a basin and the synthetic station. Alarms are set on the FhitNovaScoreMax stations to result in novascores of 6-13. The NovaScore from each basin's station is associated with all the features, mapping NovaScores base on the following chart:

Because there may be so many features, it is recommended to use the cluster abilities of Operator. Circles represent a number of stations, indicated in the center of the circle. The ring around the outside of the circle indicates the percentage of features with the indicated NovaScore. For example, in the following image, of the 48 stations, approximately 1/4 - 1/3 of them have no NovaScore defined, whereas the remainder have a NovaScore of 1 (green).

During a storm event significant enough to threaten FHIT features, Operator FHIT markers may appear as below. Note the center of each cluster reflects the highest NovaScore color within the cluster, drawing attention to clusters that may only have a single elevated value.

Configuration And Technical Details

The FHIT layer uses the data-layer-geojson-fhit class.