Systems integration involves the development and deployment of a framework through which disparate systems can communicate and share data seamlessly, facilitate data query, perform analyses, and report. The scale and breadth of our products range from simple spreadsheet-based tools like EPA's STEPL (for estimating pollutant loads) to complex but seamless integration of several individual systems into unified frameworks such as web-based MDEQ Surface Water Information Management System (SWIMS) and EPA's BASINS.   Data analysis and visualization is the overlay, manipulation, analysis, interpretation, and presentation of data layers to effectively communicate information to end users. The Index of Watershed Indicators (IWI) compiled and analyzed several national GIS databases to arrive at composite indicators of the water quality condition and pollution vulnerability of all the nation's watersheds. The Maryland Integrated Watershed Analysis and Management System (IWAMS) provides an ESRI ArcView-based decision support system for watershed prioritization and BMP targeting. Tetra Tech developed both the IWI and IWAMS. Back to top Web services development involves the development and deployment of web sites and web applications for access to and delivery of database and document resources for Internet and Intranet users. The Tribal Information Management System (TIMS) web site provides EPA and tribal users access to environmental data related to the tribes through data mining, dynamic maps, and reports. The Surface Water Information Management System (SWIMS) web site provides Intranet users of MDEQ easy access to their geospatial database. The CWNS and Beach web sites were created to support the 2000 Clean Water Needs Survey and beach survey, respectively. Back to top Database and interface development involves developing new and enhancing existing databases, as well as developing graphical user interfaces for data editing, browsing, and querying. Tetra Tech has developed databases and interfaces in Oracle and MS Access for federal and local clients, including the TMDL Tracking, Agricultural BMP, and Clean Water Needs Survey (CWNS) databases for EPA; the Environmental Data Analysis System (EDAS) for various state agencies; the Ultra-Urban BMP database for the DOT Federal Highway Administration; the Water Quality Monitoring Database for Washington Suburban Sanitary Commission; and the Sewer and Water Database for Prince George's County in Maryland. Back to top Model and interface development involves developing new scientific models, improving existing ones, and developing graphical user interfaces to facilitate their use and the interpretation of model results. Tetra Tech's expertise ranges from screening-level models to complex, numerically rigorous hydrodynamic and water quality models. To date Tetra Tech has developed graphical user interfaces for HSPF, QUAL2E, EFDC, SWMM, GLEAMS, SWAT, and GWLF. We're currently developing a modeling toolbox to facilitate data sharing and communications among models, including EFDC, LSPC, WAM, WASP, and new watershed models such as sediment budget and mercury load models. Tetra Tech also is developing applications to support field data collection efforts using hand-held devices. Geographic information systems involve integrating spatial analysis and mapping capabilities with traditional analytical methods and systems. GIS is a strong component of each the above-mentioned IT services, from seamlessly integrating geographic data with business and programmatic data to enhancing visualization methods through maps and animation. In support of our core environmental and water resources services, we have effectively used GIS to deliver better and faster products and services to our clients. Back to top