diff --git a/.strict-typing b/.strict-typing
index be6f540e633..2929550ffa8 100644
--- a/.strict-typing
+++ b/.strict-typing
@@ -386,6 +386,7 @@ homeassistant.components.pandora.*
 homeassistant.components.panel_custom.*
 homeassistant.components.peblar.*
 homeassistant.components.peco.*
+homeassistant.components.pegel_online.*
 homeassistant.components.persistent_notification.*
 homeassistant.components.person.*
 homeassistant.components.pi_hole.*
diff --git a/homeassistant/components/pegel_online/sensor.py b/homeassistant/components/pegel_online/sensor.py
index fd90683a9b2..981ee4ff469 100644
--- a/homeassistant/components/pegel_online/sensor.py
+++ b/homeassistant/components/pegel_online/sensor.py
@@ -2,9 +2,10 @@
 
 from __future__ import annotations
 
+from collections.abc import Callable
 from dataclasses import dataclass
 
-from aiopegelonline.models import CurrentMeasurement
+from aiopegelonline.models import CurrentMeasurement, StationMeasurements
 
 from homeassistant.components.sensor import (
     SensorDeviceClass,
@@ -24,67 +25,67 @@ from .entity import PegelOnlineEntity
 class PegelOnlineSensorEntityDescription(SensorEntityDescription):
     """PEGELONLINE sensor entity description."""
 
-    measurement_key: str
+    measurement_fn: Callable[[StationMeasurements], CurrentMeasurement | None]
 
 
 SENSORS: tuple[PegelOnlineSensorEntityDescription, ...] = (
     PegelOnlineSensorEntityDescription(
         key="air_temperature",
         translation_key="air_temperature",
-        measurement_key="air_temperature",
         state_class=SensorStateClass.MEASUREMENT,
         device_class=SensorDeviceClass.TEMPERATURE,
         entity_registry_enabled_default=False,
+        measurement_fn=lambda data: data.air_temperature,
     ),
     PegelOnlineSensorEntityDescription(
         key="clearance_height",
         translation_key="clearance_height",
-        measurement_key="clearance_height",
         state_class=SensorStateClass.MEASUREMENT,
         device_class=SensorDeviceClass.DISTANCE,
+        measurement_fn=lambda data: data.clearance_height,
     ),
     PegelOnlineSensorEntityDescription(
         key="oxygen_level",
         translation_key="oxygen_level",
-        measurement_key="oxygen_level",
         state_class=SensorStateClass.MEASUREMENT,
         entity_registry_enabled_default=False,
+        measurement_fn=lambda data: data.oxygen_level,
     ),
     PegelOnlineSensorEntityDescription(
         key="ph_value",
-        measurement_key="ph_value",
         state_class=SensorStateClass.MEASUREMENT,
         device_class=SensorDeviceClass.PH,
         entity_registry_enabled_default=False,
+        measurement_fn=lambda data: data.ph_value,
     ),
     PegelOnlineSensorEntityDescription(
         key="water_speed",
         translation_key="water_speed",
-        measurement_key="water_speed",
         state_class=SensorStateClass.MEASUREMENT,
         device_class=SensorDeviceClass.SPEED,
         entity_registry_enabled_default=False,
+        measurement_fn=lambda data: data.water_speed,
     ),
     PegelOnlineSensorEntityDescription(
         key="water_flow",
         translation_key="water_flow",
-        measurement_key="water_flow",
         state_class=SensorStateClass.MEASUREMENT,
         entity_registry_enabled_default=False,
+        measurement_fn=lambda data: data.water_flow,
     ),
     PegelOnlineSensorEntityDescription(
         key="water_level",
         translation_key="water_level",
-        measurement_key="water_level",
         state_class=SensorStateClass.MEASUREMENT,
+        measurement_fn=lambda data: data.water_level,
     ),
     PegelOnlineSensorEntityDescription(
         key="water_temperature",
         translation_key="water_temperature",
-        measurement_key="water_temperature",
         state_class=SensorStateClass.MEASUREMENT,
         device_class=SensorDeviceClass.TEMPERATURE,
         entity_registry_enabled_default=False,
+        measurement_fn=lambda data: data.water_temperature,
     ),
 )
 
@@ -101,7 +102,7 @@ async def async_setup_entry(
         [
             PegelOnlineSensor(coordinator, description)
             for description in SENSORS
-            if getattr(coordinator.data, description.measurement_key) is not None
+            if description.measurement_fn(coordinator.data) is not None
         ]
     )
 
@@ -135,7 +136,9 @@ class PegelOnlineSensor(PegelOnlineEntity, SensorEntity):
     @property
     def measurement(self) -> CurrentMeasurement:
         """Return the measurement data of the entity."""
-        return getattr(self.coordinator.data, self.entity_description.measurement_key)
+        measurement = self.entity_description.measurement_fn(self.coordinator.data)
+        assert measurement is not None  # we ensure existence in async_setup_entry
+        return measurement
 
     @property
     def native_value(self) -> float:
diff --git a/mypy.ini b/mypy.ini
index 5c6db87590f..eb5af1fd76c 100644
--- a/mypy.ini
+++ b/mypy.ini
@@ -3616,6 +3616,16 @@ disallow_untyped_defs = true
 warn_return_any = true
 warn_unreachable = true
 
+[mypy-homeassistant.components.pegel_online.*]
+check_untyped_defs = true
+disallow_incomplete_defs = true
+disallow_subclassing_any = true
+disallow_untyped_calls = true
+disallow_untyped_decorators = true
+disallow_untyped_defs = true
+warn_return_any = true
+warn_unreachable = true
+
 [mypy-homeassistant.components.persistent_notification.*]
 check_untyped_defs = true
 disallow_incomplete_defs = true