From 7c36be65e885644bfd48ecd764f56bc2383c67c8 Mon Sep 17 00:00:00 2001
From: kbonney <kirkb1998@gmail.com>
Date: Tue, 12 Mar 2024 11:23:20 -0400
Subject: [PATCH] fix: added if statement to catch when "SI" is provided as a
 unit to write inp

---
 wntr/epanet/io.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/wntr/epanet/io.py b/wntr/epanet/io.py
index c2f615fcd..43d580c70 100644
--- a/wntr/epanet/io.py
+++ b/wntr/epanet/io.py
@@ -434,6 +434,8 @@ def write(self, filename, wn, units=None, version=2.2, force_coordinates=False):
             raise ValueError('Must pass a WaterNetworkModel object')
         if units is not None and isinstance(units, str):
             units=units.upper()
+            if units=="SI":
+                raise Exception("unit cannot be 'SI'")
             self.flow_units = FlowUnits[units]
         elif units is not None and isinstance(units, FlowUnits):
             self.flow_units = units