diff --git a/tool_statistics/presets.py b/tool_statistics/presets.py
index d8a4ee79..e3a39fab 100644
--- a/tool_statistics/presets.py
+++ b/tool_statistics/presets.py
@@ -104,8 +104,8 @@ def aggregations(self):
 CHANGE_WL_PRESETS = Preset(
     name="Change in water level",
     description="Calculates the difference in water level (last - first). In the styling "
-    "NULL values (when the cell is dry) are replaced by the cells lowest "
-    "pixel elevation (z_coordinate).",
+    "NULL values (when the cell is dry) are replaced by the cell's lowest "
+    "pixel elevation (bottom_level).",
     aggregations=change_wl_aggregations,
     cells_style=STYLE_CHANGE_WL,
     cells_style_param_values={"first": "s1_first", "last": "s1_last"},
@@ -256,7 +256,7 @@ def aggregations(self):
 
 WATER_ON_STREET_DURATION_PRESET = Preset(
     name="Water on street duration",
-    description="Duration of waterlevel above manhole drain level.",
+    description="Duration of water level above manhole drain level.",
     aggregations=water_on_street_aggregations,
     nodes_style=STYLE_WATER_ON_STREET_DURATION_NODE,
     nodes_style_param_values={"column": "s1_time_above_threshold"},
diff --git a/tool_statistics/style.py b/tool_statistics/style.py
index 42b56a2f..2484451b 100644
--- a/tool_statistics/style.py
+++ b/tool_statistics/style.py
@@ -108,7 +108,7 @@ def style_change_water_level(layer, qml: str, first: str, last: str):
 
     layer.loadNamedStyle(qml)
     class_attribute_string = (
-        f"((coalesce({last}, z_coordinate))-(coalesce({first}, z_coordinate)))"
+        f"((coalesce({last}, bottom_level))-(coalesce({first}, bottom_level)))"
     )
     layer.renderer().setClassAttribute(class_attribute_string)
     # layer.renderer().deleteAllClasses()
diff --git a/tool_statistics/style/change_water_level.qml b/tool_statistics/style/change_water_level.qml
index f66c07ad..f52b2f77 100644
--- a/tool_statistics/style/change_water_level.qml
+++ b/tool_statistics/style/change_water_level.qml
@@ -1,11 +1,6 @@
 <!DOCTYPE qgis PUBLIC 'http://mrcc.com/qgis.dtd' 'SYSTEM'>
 <qgis version="3.10.10-A Coruña" minScale="1e+08" simplifyDrawingTol="1" simplifyLocal="1" hasScaleBasedVisibilityFlag="0" maxScale="0" simplifyDrawingHints="1" styleCategories="AllStyleCategories" simplifyMaxScale="1" readOnly="0" labelsEnabled="0" simplifyAlgorithm="0">
-  <flags>
-    <Identifiable>1</Identifiable>
-    <Removable>1</Removable>
-    <Searchable>1</Searchable>
-  </flags>
-  <renderer-v2 symbollevels="0" graduatedMethod="GraduatedColor" type="graduatedSymbol" forceraster="0" enableorderby="0" attr="((coalesce(s1_last, z_coordinate))-(coalesce(s1_first, z_coordinate)))">
+  <renderer-v2 symbollevels="0" graduatedMethod="GraduatedColor" type="graduatedSymbol" forceraster="0" enableorderby="0" attr="((coalesce(s1_last, bottom_level))-(coalesce(s1_first, bottom_level)))">
     <ranges>
       <range label="&lt; -2" upper="-2.000000000000000" lower="-99999999.000000000000000" render="true" symbol="0"/>
       <range label="-2 - -1 " upper="-1.000000000000000" lower="-2.000000000000000" render="true" symbol="1"/>
@@ -440,221 +435,4 @@
     <rotation/>
     <sizescale/>
   </renderer-v2>
-  <customproperties>
-    <property value="id" key="dualview/previewExpressions"/>
-    <property value="0" key="embeddedWidgets/count"/>
-    <property key="variableNames"/>
-    <property key="variableValues"/>
-  </customproperties>
-  <blendMode>0</blendMode>
-  <featureBlendMode>0</featureBlendMode>
-  <layerOpacity>1</layerOpacity>
-  <SingleCategoryDiagramRenderer attributeLegend="1" diagramType="Histogram">
-    <DiagramCategory minScaleDenominator="0" penWidth="0" sizeScale="3x:0,0,0,0,0,0" sizeType="MM" backgroundAlpha="255" penColor="#000000" diagramOrientation="Up" labelPlacementMethod="XHeight" opacity="1" scaleBasedVisibility="0" penAlpha="255" backgroundColor="#ffffff" lineSizeScale="3x:0,0,0,0,0,0" rotationOffset="270" enabled="0" minimumSize="0" height="15" width="15" maxScaleDenominator="1e+08" scaleDependency="Area" barWidth="5" lineSizeType="MM">
-      <fontProperties style="" description="MS Shell Dlg 2,7.8,-1,5,50,0,0,0,0,0"/>
-      <attribute label="" field="" color="#000000"/>
-    </DiagramCategory>
-  </SingleCategoryDiagramRenderer>
-  <DiagramLayerSettings placement="1" priority="0" showAll="1" zIndex="0" obstacle="0" dist="0" linePlacementFlags="18">
-    <properties>
-      <Option type="Map">
-        <Option name="name" type="QString" value=""/>
-        <Option name="properties"/>
-        <Option name="type" type="QString" value="collection"/>
-      </Option>
-    </properties>
-  </DiagramLayerSettings>
-  <geometryOptions removeDuplicateNodes="0" geometryPrecision="0">
-    <activeChecks/>
-    <checkConfiguration type="Map">
-      <Option name="QgsGeometryGapCheck" type="Map">
-        <Option name="allowedGapsBuffer" type="double" value="0"/>
-        <Option name="allowedGapsEnabled" type="bool" value="false"/>
-        <Option name="allowedGapsLayer" type="QString" value=""/>
-      </Option>
-    </checkConfiguration>
-  </geometryOptions>
-  <fieldConfiguration>
-    <field name="id">
-      <editWidget type="Range">
-        <config>
-          <Option/>
-        </config>
-      </editWidget>
-    </field>
-    <field name="node_type">
-      <editWidget type="Range">
-        <config>
-          <Option/>
-        </config>
-      </editWidget>
-    </field>
-    <field name="node_type_description">
-      <editWidget type="TextEdit">
-        <config>
-          <Option/>
-        </config>
-      </editWidget>
-    </field>
-    <field name="z_coordinate">
-      <editWidget type="TextEdit">
-        <config>
-          <Option/>
-        </config>
-      </editWidget>
-    </field>
-    <field name="s1_first">
-      <editWidget type="TextEdit">
-        <config>
-          <Option/>
-        </config>
-      </editWidget>
-    </field>
-    <field name="s1_last">
-      <editWidget type="TextEdit">
-        <config>
-          <Option/>
-        </config>
-      </editWidget>
-    </field>
-    <field name="s1_min">
-      <editWidget type="TextEdit">
-        <config>
-          <Option/>
-        </config>
-      </editWidget>
-    </field>
-    <field name="s1_max">
-      <editWidget type="TextEdit">
-        <config>
-          <Option/>
-        </config>
-      </editWidget>
-    </field>
-  </fieldConfiguration>
-  <aliases>
-    <alias name="" field="id" index="0"/>
-    <alias name="" field="node_type" index="1"/>
-    <alias name="" field="node_type_description" index="2"/>
-    <alias name="" field="z_coordinate" index="3"/>
-    <alias name="" field="s1_first" index="4"/>
-    <alias name="" field="s1_last" index="5"/>
-    <alias name="" field="s1_min" index="6"/>
-    <alias name="" field="s1_max" index="7"/>
-  </aliases>
-  <excludeAttributesWMS/>
-  <excludeAttributesWFS/>
-  <defaults>
-    <default applyOnUpdate="0" field="id" expression=""/>
-    <default applyOnUpdate="0" field="node_type" expression=""/>
-    <default applyOnUpdate="0" field="node_type_description" expression=""/>
-    <default applyOnUpdate="0" field="z_coordinate" expression=""/>
-    <default applyOnUpdate="0" field="s1_first" expression=""/>
-    <default applyOnUpdate="0" field="s1_last" expression=""/>
-    <default applyOnUpdate="0" field="s1_min" expression=""/>
-    <default applyOnUpdate="0" field="s1_max" expression=""/>
-  </defaults>
-  <constraints>
-    <constraint exp_strength="0" constraints="0" field="id" unique_strength="0" notnull_strength="0"/>
-    <constraint exp_strength="0" constraints="0" field="node_type" unique_strength="0" notnull_strength="0"/>
-    <constraint exp_strength="0" constraints="0" field="node_type_description" unique_strength="0" notnull_strength="0"/>
-    <constraint exp_strength="0" constraints="0" field="z_coordinate" unique_strength="0" notnull_strength="0"/>
-    <constraint exp_strength="0" constraints="0" field="s1_first" unique_strength="0" notnull_strength="0"/>
-    <constraint exp_strength="0" constraints="0" field="s1_last" unique_strength="0" notnull_strength="0"/>
-    <constraint exp_strength="0" constraints="0" field="s1_min" unique_strength="0" notnull_strength="0"/>
-    <constraint exp_strength="0" constraints="0" field="s1_max" unique_strength="0" notnull_strength="0"/>
-  </constraints>
-  <constraintExpressions>
-    <constraint exp="" desc="" field="id"/>
-    <constraint exp="" desc="" field="node_type"/>
-    <constraint exp="" desc="" field="node_type_description"/>
-    <constraint exp="" desc="" field="z_coordinate"/>
-    <constraint exp="" desc="" field="s1_first"/>
-    <constraint exp="" desc="" field="s1_last"/>
-    <constraint exp="" desc="" field="s1_min"/>
-    <constraint exp="" desc="" field="s1_max"/>
-  </constraintExpressions>
-  <expressionfields/>
-  <attributeactions>
-    <defaultAction value="{00000000-0000-0000-0000-000000000000}" key="Canvas"/>
-  </attributeactions>
-  <attributetableconfig sortOrder="0" actionWidgetStyle="dropDown" sortExpression="">
-    <columns>
-      <column name="id" width="-1" hidden="0" type="field"/>
-      <column width="-1" hidden="1" type="actions"/>
-      <column name="node_type" width="-1" hidden="0" type="field"/>
-      <column name="node_type_description" width="-1" hidden="0" type="field"/>
-      <column name="z_coordinate" width="-1" hidden="0" type="field"/>
-      <column name="s1_first" width="-1" hidden="0" type="field"/>
-      <column name="s1_max" width="-1" hidden="0" type="field"/>
-      <column name="s1_min" width="-1" hidden="0" type="field"/>
-      <column name="s1_last" width="-1" hidden="0" type="field"/>
-    </columns>
-  </attributetableconfig>
-  <conditionalstyles>
-    <rowstyles/>
-    <fieldstyles/>
-  </conditionalstyles>
-  <storedexpressions/>
-  <editform tolerant="1"></editform>
-  <editforminit/>
-  <editforminitcodesource>0</editforminitcodesource>
-  <editforminitfilepath></editforminitfilepath>
-  <editforminitcode><![CDATA[# -*- coding: utf-8 -*-
-"""
-QGIS forms can have a Python function that is called when the form is
-opened.
-
-Use this function to add extra logic to your forms.
-
-Enter the name of the function in the "Python Init function"
-field.
-An example follows:
-"""
-from qgis.PyQt.QtWidgets import QWidget
-
-def my_form_open(dialog, layer, feature):
-	geom = feature.geometry()
-	control = dialog.findChild(QWidget, "MyLineEdit")
-]]></editforminitcode>
-  <featformsuppress>0</featformsuppress>
-  <editorlayout>generatedlayout</editorlayout>
-  <editable>
-    <field name="fid" editable="1"/>
-    <field name="id" editable="1"/>
-    <field name="infiltration_rate_mm_sum" editable="1"/>
-    <field name="intercepted_volume_mm_last" editable="1"/>
-    <field name="node_type" editable="1"/>
-    <field name="node_type_description" editable="1"/>
-    <field name="q_out_x_sum" editable="1"/>
-    <field name="q_out_y_sum" editable="1"/>
-    <field name="rain_depth_sum" editable="1"/>
-    <field name="s1_first" editable="1"/>
-    <field name="s1_last" editable="1"/>
-    <field name="s1_max" editable="1"/>
-    <field name="s1_min" editable="1"/>
-    <field name="spatialite_id" editable="1"/>
-    <field name="z_coordinate" editable="1"/>
-  </editable>
-  <labelOnTop>
-    <field name="fid" labelOnTop="0"/>
-    <field name="id" labelOnTop="0"/>
-    <field name="infiltration_rate_mm_sum" labelOnTop="0"/>
-    <field name="intercepted_volume_mm_last" labelOnTop="0"/>
-    <field name="node_type" labelOnTop="0"/>
-    <field name="node_type_description" labelOnTop="0"/>
-    <field name="q_out_x_sum" labelOnTop="0"/>
-    <field name="q_out_y_sum" labelOnTop="0"/>
-    <field name="rain_depth_sum" labelOnTop="0"/>
-    <field name="s1_first" labelOnTop="0"/>
-    <field name="s1_last" labelOnTop="0"/>
-    <field name="s1_max" labelOnTop="0"/>
-    <field name="s1_min" labelOnTop="0"/>
-    <field name="spatialite_id" labelOnTop="0"/>
-    <field name="z_coordinate" labelOnTop="0"/>
-  </labelOnTop>
-  <widgets/>
-  <previewExpression>"id"</previewExpression>
-  <mapTip></mapTip>
-  <layerGeometryType>2</layerGeometryType>
-</qgis>
+</qgis>
\ No newline at end of file