diff --git a/app/config.py b/app/config.py
index ab999945f..b49411164 100644
--- a/app/config.py
+++ b/app/config.py
@@ -127,7 +127,7 @@ class Config(object):
     SQLALCHEMY_COMMIT_ON_TEARDOWN = False
     SQLALCHEMY_RECORD_QUERIES = True
     SQLALCHEMY_TRACK_MODIFICATIONS = True
-    SQLALCHEMY_POOL_SIZE = os.environ.get('SQLALCHEMY_POOL_SIZE', 5)
+    SQLALCHEMY_POOL_SIZE = int(os.environ.get('SQLALCHEMY_POOL_SIZE', 5))
     SQLALCHEMY_POOL_TIMEOUT = 30
     SQLALCHEMY_POOL_RECYCLE = 300
     PAGE_SIZE = 50