diff --git a/swh/loader/svn/loader.py b/swh/loader/svn/loader.py
--- a/swh/loader/svn/loader.py
+++ b/swh/loader/svn/loader.py
@@ -7,6 +7,7 @@
 swh-storage.
 
 """
+from datetime import datetime
 from mmap import ACCESS_WRITE, mmap
 import os
 import pty
@@ -16,8 +17,6 @@
 import tempfile
 from typing import Dict, Iterator, List, Optional, Tuple
 
-import iso8601
-
 from subvertpy import SubversionException
 
 from swh.loader.core.loader import BaseLoader
@@ -67,7 +66,7 @@
         storage: StorageInterface,
         url: str,
         origin_url: Optional[str] = None,
-        visit_date: Optional[str] = None,
+        visit_date: Optional[datetime] = None,
         destination_path: Optional[str] = None,
         swh_revision: Optional[str] = None,
         start_from_scratch: bool = False,
@@ -101,10 +100,7 @@
         self._last_revision = None
         self._visit_status = "full"
         self._load_status = "uneventful"
-        if visit_date:
-            self.visit_date = iso8601.parse_date(visit_date)
-        else:
-            self.visit_date = None
+        self.visit_date = visit_date
         self.destination_path = destination_path
         self.start_from_scratch = start_from_scratch
         self.snapshot = None
@@ -555,7 +551,7 @@
         destination_path: Optional[str] = None,
         swh_revision: Optional[str] = None,
         start_from_scratch: bool = False,
-        visit_date: Optional[str] = None,
+        visit_date: Optional[datetime] = None,
         temp_directory: str = "/tmp",
         debug: bool = False,
         check_revision: Optional[int] = None,
@@ -614,7 +610,7 @@
         destination_path: Optional[str] = None,
         swh_revision: Optional[str] = None,
         start_from_scratch: bool = False,
-        visit_date: Optional[str] = None,
+        visit_date: Optional[datetime] = None,
         temp_directory: str = "/tmp",
         debug: bool = False,
         check_revision: Optional[int] = None,
diff --git a/swh/loader/svn/tasks.py b/swh/loader/svn/tasks.py
--- a/swh/loader/svn/tasks.py
+++ b/swh/loader/svn/tasks.py
@@ -3,13 +3,24 @@
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
+from datetime import datetime
 from typing import Optional
 
 from celery import shared_task
+import iso8601
 
 from .loader import SvnLoader, SvnLoaderFromDumpArchive, SvnLoaderFromRemoteDump
 
 
+def convert_to_datetime(date: Optional[str]) -> Optional[datetime]:
+    if not date:
+        return None
+    try:
+        return iso8601.parse_date(date)
+    except Exception:
+        return None
+
+
 @shared_task(name=__name__ + ".LoadSvnRepository")
 def load_svn(
     *,
@@ -41,7 +52,7 @@
         origin_url=origin_url,
         destination_path=destination_path,
         swh_revision=swh_revision,
-        visit_date=visit_date,
+        visit_date=convert_to_datetime(visit_date),
         start_from_scratch=start_from_scratch,
     )
     return loader.load()
@@ -70,7 +81,7 @@
     loader = SvnLoaderFromDumpArchive.from_configfile(
         url=url,
         archive_path=archive_path,
-        visit_date=visit_date,
+        visit_date=convert_to_datetime(visit_date),
         start_from_scratch=start_from_scratch,
     )
     return loader.load()
@@ -100,7 +111,7 @@
     loader = SvnLoaderFromRemoteDump.from_configfile(
         url=url,
         origin_url=origin_url,
-        visit_date=visit_date,
+        visit_date=convert_to_datetime(visit_date),
         start_from_scratch=start_from_scratch,
     )
     return loader.load()