diff --git a/cmake/std/atdm/waterman/environment.sh b/cmake/std/atdm/waterman/environment.sh
index 7c971f787b34..b32ef020c75b 100755
--- a/cmake/std/atdm/waterman/environment.sh
+++ b/cmake/std/atdm/waterman/environment.sh
@@ -146,8 +146,8 @@ elif [[ "$ATDM_CONFIG_COMPILER" == "CUDA"* ]] ; then
   export CUDA_LAUNCH_BLOCKING=1
   export CUDA_MANAGED_FORCE_DEVICE_ALLOC=1
   export KOKKOS_NUM_DEVICES=2
-  export ATDM_CONFIG_CTEST_PARALLEL_LEVEL=4
-  # Avoids timeouts due to not running on separate GPUs (see #2446)
+  export ATDM_CONFIG_CTEST_PARALLEL_LEVEL=2
+  # Avoids timeouts due to not running on separate GPUs (e.g. see #2446)
 
 fi