<?xml version="1.0" encoding="UTF-8"?>
<xsd:schema version="5.0" 
            xmlns:nwis="http://water.usgs.gov/XML/NWIS/5.0"
            
            xmlns:xsd="http://www.w3.org/2001/XMLSchema"
            
            elementFormDefault="qualified">
   <xsd:simpleType name="PartialDateType">
      <xsd:annotation>
         <xsd:documentation/>
      </xsd:annotation>
      <xsd:union>
         <xsd:simpleType>
            <xsd:restriction base="xsd:date"/>
         </xsd:simpleType>
         <xsd:simpleType>
            <xsd:restriction base="xsd:gYearMonth"/>
         </xsd:simpleType>
         <xsd:simpleType>
            <xsd:restriction base="xsd:gYear"/>
         </xsd:simpleType>
      </xsd:union>
   </xsd:simpleType>
</xsd:schema>