diff --git a/transfers/well_transfer.py b/transfers/well_transfer.py
index 50ea868b3..2aa70ba01 100644
--- a/transfers/well_transfer.py
+++ b/transfers/well_transfer.py
@@ -624,15 +624,15 @@ def _after_hook(self, session):
         measuring_point_estimator = MeasuringPointEstimator()
         # add things thate need well id
         query = session.query(Thing).filter(Thing.thing_type == "water well")
-        count = query.count()
-        wells = query.all()
-        # for j, chunk in enumerate(chunk_by_size(query.all(), 100)):
         chunk_size = 100
-        for j, chunki in enumerate(range(0, count, chunk_size)):
-            chunk = wells[chunki : chunki + chunk_size]
+        count = query.count()
+        processed = 0
+        chunk = []
+
+        def _process_chunk(chunk_index: int, wells_chunk: list[Thing]):
             step_start_time = time.time()
             all_objects = []
-            for i, well in enumerate(chunk):
+            for well in wells_chunk:
                 objs = self._after_hook_chunk(
                     well, formations, measuring_point_estimator
                 )
@@ -649,10 +649,21 @@ def _after_hook(self, session):
             finally:
                 save_time = time.time() - save_time
 
+            processed_count = chunk_index * chunk_size + len(wells_chunk)
             logger.info(
-                f"After hook: {(j+1)*100}/{count} took {time.time() - step_start_time:.2f}s, "
+                f"After hook: {processed_count}/{count} took {time.time() - step_start_time:.2f}s, "
                 f"n_objects={len(all_objects)}, save_time={save_time}"
             )
+            return processed_count
+
+        for well in query.yield_per(chunk_size):
+            chunk.append(well)
+            if len(chunk) == chunk_size:
+                processed = _process_chunk(processed // chunk_size, chunk)
+                chunk = []
+
+        if chunk:
+            _process_chunk(processed // chunk_size, chunk)
 
     def _after_hook_chunk(self, well, formations, measuring_point_estimator):