From f1232527193845aad73d68996c372b4a6988e3cb Mon Sep 17 00:00:00 2001
From: rania-pa <65612652+rania-pa@users.noreply.github.com>
Date: Wed, 26 Jul 2023 00:42:53 +0100
Subject: [PATCH] Update add_surface_water.py

---
 gprMax/cmds_geometry/add_surface_water.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gprMax/cmds_geometry/add_surface_water.py b/gprMax/cmds_geometry/add_surface_water.py
index 5bef6478..47e1f654 100644
--- a/gprMax/cmds_geometry/add_surface_water.py
+++ b/gprMax/cmds_geometry/add_surface_water.py
@@ -156,7 +156,7 @@ class AddSurfaceWater(UserObjectGeometry):
             raise ValueError
 
         # Check to see if water has been already defined as a material
-        if not any(x.ID != "water" for x in grid.materials):
+        if not any(x.ID == "water" for x in grid.materials):
             create_water(grid)
 
         # Check if time step for model is suitable for using water