State Management :: Viewstate And Dropdownlist / Initial Selection Is Lost Each Time The Page Refreshes

I have a simple search page with a drop down list that I would like the value to persist on refresh..basically the user will select their location from the dropdownlist and this will be used to populate a gridview. After this the page is set to refresh at a set interval and use the same location data initially selected by the user. However the initial selection is lost each time the page refreshes.

p.s system is to old for ajax!

<meta http-equiv="Refresh" content="300" />
<script runat="server">
Dim connectionString As String = ConfigurationManager.ConnectionStrings("****").ConnectionString
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs)
If Not IsPostBack Then
Dim conn As SqlConnection
conn = New SqlConnection(connectionString)
Dim Locationcommandtext As String
Locationcommandtext = "SELECT * FROM [Location] ORDER BY [Location]"
Dim loccomm As SqlCommand
loccomm = New SqlCommand(Locationcommandtext, conn)
Dim reader As SqlDataReader
Try
conn.Open()
reader = loccomm.ExecuteReader()
Locations.DataSource = reader
Locations.DataValueField = "LocationID"
Locations.DataTextField = "Location"
Locations.DataBind()
Catch ex As SqlException
Response.Write("SQL Error:
" & ex.ToString())
Finally
conn.Close()
End Try
Else
'"Viewstate should kick in here"
End If
End Sub
</script>