A declaration of identity certifies that all of the services which are used by a property are located within the relevant site boundary of the property. Such services generally include a septic tank or treatment systems and percolation area, the dwelling house and ancillary works and a private supply water well. The declaration of identity is often requested by solicitors in order to ensure that no significant issues arise in the future with regard to access to these services. The declaration refers to a folio number and is accompanied by the Folio map or Ordnance Survey Land Registry Map outlining the site in red.