PARENT SESSION

1L - Exposure Modelling
Poster Hall
8:30 AM - Wednesday, 30 April 2003
Chair: Lammel, G.¹, ¹
Co-chair: Dachs, J.², ²

(WEP/76) GIS-ROUT - A National Watershed Model for Exposure Assessment.

Dyer, Scott¹, Cowan-Ellsberry, Christina ¹, White-Hull, Charlotte¹, Homer, Michael¹, Wang, Xinhao², ¹ Procter & Gamble Company, Cincinnati, Ohio, USA² University of Cincinnati, Cincinnati, Ohio, USA

ABSTRACT- In 1987, the exposure model GIS-ROUT was developed by P&G to determine concentrations of user-defined and conventional pollutants using river, industry, and wastewater treatment plant (WWTP) discharge descriptors, and chemical loading data. The model is currently parameterized for the U.S.; however its algorithms are applicable to other geographies. When developed, GIS-ROUT differed from other models by incorporating cumulative discharges over broad geographic areas. However, technical issues such as data volume, platform, performance, and ease of use prevented its widespread distribution. Thus, GIS-ROUT was redesigned to address these limitations and provide additional functionality. Driving the redesign is a Geographic Information Systems (GIS) and Web-based architecture. In the new system, rivers are modeled from headwater to estuary using the RF1 network, and are segmented at tributaries, WWTPs, and drinking water intakes. At these breakpoints, in-stream concentrations are derived using upstream concentrations, industry and population-based WWTP loadings, and in-stream loss and dilution. Using consumer product monitoring data, the model algorithm was shown to predict concentrations within a factor of two. The GIS-ROUT system architecture facilitates analyses at the watershed, regional, and national scales; input of sales-based chemical loadings; and overlays with other spatial data sets (e.g. biology, habitat), enabling eco-epidemiological investigations. Other advantages of this platform include a central data repository, and ready portability. Applications of GIS-ROUT to chemicals with varying physical/chemical properties will be discussed.

Key words: watershed model, water quality, chemical exposure, consumer product