Saltwater Intrusion Model

A groundwater flow model that simulates saltwater intrusion into a coastal aquifer using variable-density flow.

Problem Description

Create a simple 2D cross-section model to simulate saltwater intrusion in a coastal aquifer. The model represents a vertical slice from inland (left) to ocean (right).

Model specifications:

• Grid: 50 columns × 1 row × 20 layers
• Cell dimensions: 10 m wide × 10 m long × 1 m thick
• Simulation: Steady-state (1 stress period, 1 time step, 1 day)
• Hydraulic conductivity: 10 m/day (uniform, isotropic)
• Boundary conditions:
  • Left side (inland): Constant head = 10.0 m
  • Right side (ocean): Constant head = 0.0 m
• Initial heads: 5.0 m everywhere
• Reference density (freshwater): 1000 kg/m³
• Saltwater density: 1025 kg/m³
• Density slope: 0.025 (kg/m³ per kg/m³ of concentration)

Requirements

Model Setup

• It creates a MODFLOW 6 simulation with time discretization @test
• It sets up a structured grid (DIS) with specified dimensions @test
• It configures initial conditions (IC) @test

Flow Packages

• It adds the Node Property Flow (NPF) package with hydraulic conductivity @test
• It adds the Storage (STO) package for transient storage @test
• It adds Constant Head (CHD) boundaries on left and right sides @test

Variable-Density Flow

• It adds the Buoyancy (BUY) package to the model @test
• It configures reference density for freshwater @test
• It specifies density slope for concentration-density relationship @test

Solution

• It adds the IMS solver package @test
• It configures output control (OC) for saving heads @test

Implementation

@generates

API

def create_saltwater_intrusion_model(workspace='./saltwater_sim'):
    """
    Creates a MODFLOW 6 model for simulating saltwater intrusion using variable-density flow.

    Args:
        workspace: Directory path where simulation files will be written

    Returns:
        sim: The configured MFSimulation object
    """
    pass

Dependencies { .dependencies }

flopy { .dependency }

Provides MODFLOW 6 modeling capabilities including the Buoyancy package for variable-density flow simulations.