Getting Started with the QUAL2K Web Wizard

The QUAL2K Web Wizard guides you through all required input data in 10 sequential cards, based on the EPA QUAL2K framework. Each card covers a distinct aspect of the model configuration, from project metadata to simulation execution and results review.

The 10-Card Wizard Flow

Step 1: Sign In

Navigate to the website and click Sign In using your Google account. Authentication is required to access the Wizard and run simulations. Your data is not stored on any server; it lives only in your browser session.

Step 2: Enter Project Data

Card 1 (Project Setup) captures the river name, simulation date, time zone, calculation step size, and integration method. The default values (Euler integration, 11.25-minute time step) work for most cases.

Step 3: Define Reaches

Card 2 (Reach Definition) is where you define the river geometry. Each reach requires:

• Name — identifier for the reach (e.g., "PR1", "VPR1")
• Downstream Distance — cumulative distance from headwater (km)
• Upstream and Downstream Elevation — for slope calculation (m)
• Manning's n — roughness coefficient (typically 0.03–0.15 for natural streams)
• Bottom Width — channel bottom width (m)
• Side Slopes — trapezoidal channel side slopes (horizontal:vertical)

Step 4: Set Headwater Boundary

Card 3 (Headwater) defines the upstream boundary condition: flow rate (m³/s), water temperature (°C), dissolved oxygen (mg/L), and concentrations for all 15 water quality constituents.

Step 5: Add Sources (Optional)

Cards 4 and 5 handle Point Sources (wastewater discharges, tributaries) and Diffuse Sources (nonpoint pollution, groundwater inflow). These are optional for simple headwater-only models.

Step 6: Configure Kinetics

Card 6 (Kinetic Rates) contains the first-order reaction rate constants for all water quality processes. Default values from the QUAL2K literature are pre-filled. See the BOD Decay and DO Balance pages for detailed explanations of each parameter.

Step 7: Import Data (Alternative)

Instead of manual entry, you can import a complete project configuration using the Import JSON or Import CSV buttons in the bottom toolbar. JSON files provide exact state restoration; CSV files enable bulk data entry from spreadsheets.

Step 8: Run the Simulation

Card 10 (Review & Run) shows a summary of all inputs and provides the simulation button. Clicking "Run Simulation" sends the wizard state to the cloud engine, which returns hydraulic and water quality results in approximately 2–5 seconds.

Step 9: Review Results

After a successful run, the results appear inline on the Review card. You can view:

• Hydraulics Summary — velocity, depth, width, area, travel time, and reaeration for each reach
• Water Quality Output — steady-state concentrations for all 15 constituents at each reach
• Raw JSON — full engine output for advanced analysis

Use the Save as JSON button to download the raw results for further processing.