<?xml version="1.0" encoding="UTF-8"?>
<xsd:schema  
            xmlns:nwis="http://water.usgs.gov/XML/NWIS/4.8" 
             
            xmlns:xsd="http://www.w3.org/2001/XMLSchema" 
            elementFormDefault="qualified" version="4.8">

  <xsd:include schemaLocation="MidSectionStation.xsd"/>
  <xsd:include schemaLocation="VelocityMeterUsed.xsd"/>
  <xsd:include schemaLocation="AdvStation.xsd"/>

  <xsd:element name="MidSectionDischargeMeasurement">
    <xsd:annotation>
      <xsd:documentation>
        <Definition>A type of discharge measurement where width, depth, and velocity measurments are performed in stations across the stream cross-section resulting in a calculated discharge.</Definition>
      </xsd:documentation>
    </xsd:annotation>
    <xsd:complexType>
      <xsd:sequence>
        <xsd:element name="StartPointCode" type="xsd:NMTOKEN">
          <xsd:annotation>
            <xsd:documentation>
              <Definition>The code indicating the starting point (left or right edge of water) of this discharge measurement section.</Definition>
            </xsd:documentation>
          </xsd:annotation>
        </xsd:element>
        <xsd:element ref="VelocityMeterUsed" minOccurs="0"/>
	<xsd:element name="AreaMeasure" type="IEEE754FloatValueType">
          <xsd:annotation>
            <xsd:documentation>
              <Definition>The area of a stream cross-section. Thne default units are in square feet.</Definition>
            </xsd:documentation>
          </xsd:annotation>
  	</xsd:element>
	<xsd:element name="WidthMeasure" type="IEEE754FloatValueType" minOccurs="0">
    	  <xsd:annotation>
      	    <xsd:documentation>
              <Definition>The width of the stream cross-section, where the measurement takes place. The default units are in feet.</Definition>
      	    </xsd:documentation>
    	  </xsd:annotation>
 	</xsd:element>
        <xsd:element name="MeanVelocityMeasure" type="IEEE754FloatValueType" minOccurs="0">
          <xsd:annotation>
            <xsd:documentation>
              <Definition>The mean stream velocity in the cross-section at the measurement section. The default units are in feet per second.</Definition>
            </xsd:documentation>
          </xsd:annotation>
        </xsd:element>
        <xsd:element name="NumberSectionsMeasure" type="xsd:nonNegativeInteger" minOccurs="0">
          <xsd:annotation>
            <xsd:documentation>
              <Definition>The number of sections measured in the discharge measurement.</Definition>
            </xsd:documentation>
          </xsd:annotation>
        </xsd:element>
        <xsd:element name="MeanObservationDuration" type="xsd:positiveInteger" minOccurs="0">
          <xsd:annotation>
            <xsd:documentation>
              <Definition>The average observation time of the velocity meter readings for a stream discharge measurement.</Definition>
            </xsd:documentation>
          </xsd:annotation>
        </xsd:element>
        <xsd:element name="VelocityObservationCode" type="xsd:string">
          <xsd:annotation>
            <xsd:documentation>
              <Definition>The code indicating the type of velocity observations made during the measurement</Definition>
            </xsd:documentation>
          </xsd:annotation>
        </xsd:element>
	<xsd:element name="HorizontalAngleIndicator" type="xsd:boolean">
          <xsd:annotation>
            <xsd:documentation>
              <Definition>Was the horizontal angle coefficient used in the discharge measurement calculations (true or false)?</Definition>
            </xsd:documentation>
          </xsd:annotation>
        </xsd:element>
        <xsd:element name="MethodCoefficientIndicator" type="xsd:boolean">
          <xsd:annotation>
            <xsd:documentation>
              <Definition>Was the the method coefficient was used in the discharge measurement calculations (true or false)?</Definition>
            </xsd:documentation>
          </xsd:annotation>
        </xsd:element>
        <xsd:element name="SuspensionCoefficientIndicator" type="xsd:boolean">
          <xsd:annotation>
            <xsd:documentation>
              <Definition>Was the suspension coefficient was used in the discharge measurement calculations (true or false)?</Definition>
            </xsd:documentation>
          </xsd:annotation>
        </xsd:element>
        <xsd:choice>
          <xsd:element ref="MidSectionStation" minOccurs="0" maxOccurs="unbounded"/>
          <xsd:element ref="AdvStation" minOccurs="0" maxOccurs="unbounded"/>
        </xsd:choice>
      </xsd:sequence>
    </xsd:complexType>
  </xsd:element>
</xsd:schema>
