diff --git a/google/cloud/firestore_v1/base_client.py b/google/cloud/firestore_v1/base_client.py
index f532ec1b7..7b9b22867 100644
--- a/google/cloud/firestore_v1/base_client.py
+++ b/google/cloud/firestore_v1/base_client.py
@@ -25,6 +25,7 @@
 """
 
 import os
+import grpc  # type: ignore
 
 import google.api_core.client_options  # type: ignore
 import google.api_core.path_template  # type: ignore
@@ -147,9 +148,7 @@ def _firestore_api_helper(self, transport, client_class, client_module) -> Any:
             # We need this in order to set appropriate keepalive options.
 
             if self._emulator_host is not None:
-                # TODO(microgen): this likely needs to be adapted to use insecure_channel
-                # on new generated surface.
-                channel = transport.create_channel(host=self._emulator_host)
+                channel = grpc.insecure_channel(self._emulator_host)
             else:
                 channel = transport.create_channel(
                     self._target,
diff --git a/noxfile.py b/noxfile.py
index 0f7922364..567f6bda2 100644
--- a/noxfile.py
+++ b/noxfile.py
@@ -27,10 +27,11 @@
 BLACK_VERSION = "black==19.10b0"
 BLACK_PATHS = ["docs", "google", "tests", "noxfile.py", "setup.py"]
 
-DEFAULT_PYTHON_VERSION = "3.9"
-SYSTEM_TEST_PYTHON_VERSIONS = ["3.9"]
+DEFAULT_PYTHON_VERSION = "3.8"
+SYSTEM_TEST_PYTHON_VERSIONS = ["3.8"]
 UNIT_TEST_PYTHON_VERSIONS = ["3.6", "3.7", "3.8", "3.9"]
 
+
 @nox.session(python=DEFAULT_PYTHON_VERSION)
 def lint(session):
     """Run linters.
@@ -98,6 +99,7 @@ def default(session):
         *session.posargs,
     )
 
+
 @nox.session(python=UNIT_TEST_PYTHON_VERSIONS)
 def unit(session):
     """Run the unit test suite."""
diff --git a/tests/unit/v1/test_base_client.py b/tests/unit/v1/test_base_client.py
index 631733e07..163ea33e7 100644
--- a/tests/unit/v1/test_base_client.py
+++ b/tests/unit/v1/test_base_client.py
@@ -67,8 +67,7 @@ def test__firestore_api_property(self, mock_channel, mock_client):
         return_value=mock.sentinel.firestore_api,
     )
     @mock.patch(
-        "google.cloud.firestore_v1.services.firestore.transports.grpc.FirestoreGrpcTransport.create_channel",
-        autospec=True,
+        "grpc.insecure_channel", autospec=True,
     )
     def test__firestore_api_property_with_emulator(
         self, mock_insecure_channel, mock_client
@@ -83,7 +82,7 @@ def test__firestore_api_property_with_emulator(
         self.assertIs(firestore_api, mock_client.return_value)
         self.assertIs(firestore_api, client._firestore_api_internal)
 
-        mock_insecure_channel.assert_called_once_with(host=emulator_host)
+        mock_insecure_channel.assert_called_once_with(emulator_host)
 
         # Call again to show that it is cached, but call count is still 1.
         self.assertIs(client._firestore_api, mock_client.return_value)