diff --git a/prms_src/prms5.2.1/prms/snowcomp.f90 b/prms_src/prms5.2.1/prms/snowcomp.f90
index 13c234e1..ef2bd151 100644
--- a/prms_src/prms5.2.1/prms/snowcomp.f90
+++ b/prms_src/prms5.2.1/prms/snowcomp.f90
@@ -2601,7 +2601,7 @@ SUBROUTINE snowevap(Potet_sublim, Potet, Snowcov_area, Snow_evap, &
           ! heat deficit
           ! JLM mass balance fix, if we take pkwater_equiv - ez below
           ! JLM we need to take ez from both pk_ice and freeh2o here
-          freeh2o = freeh2o - pk_ice
+          freeh2o = freeh2o + pk_ice
           Pk_ice = 0.0
           Pk_def = 0.0
           Pk_temp = 0.0
diff --git a/pywatershed/hydrology/prms_runoff.py b/pywatershed/hydrology/prms_runoff.py
index 9a37aded..85304316 100644
--- a/pywatershed/hydrology/prms_runoff.py
+++ b/pywatershed/hydrology/prms_runoff.py
@@ -9,11 +9,11 @@
 from ..base.control import Control
 from ..constants import (
     HruType,
+    epsilon32,
+    epsilon64,
     nan,
     numba_num_threads,
     zero,
-    epsilon32,
-    epsilon64,
 )
 from ..parameters import Parameters