SEPTIC TANK COSTS
QMy wife, Kay, and I are hoping to buy a property that we’ve identified in the Dordogne area. We are French property firsttimers with a limited knowledge of the language and need some assistance to tie down our budget. The target house requires, among other things, a new fosse septique (it presently lacks even basic toilet facilities) and we are struggling to identify who is properly qualified to undertake the specification and installation of a new fosse, and therefore obtain an accurate cost for our overall budget. We are unwilling to make an offer on the house until we’ve obtained figures for the new septic tank, and hence we are at an impasse. How can we find a tradesman who will supply and fit a suitable and compliant fosse septique?
A Non-mains drainage installations ( assainissement non collectif) comprise several elements. Pipe work takes waste from the house to the fosse tank, which ‘pre-treats’ the waste before it’s filtered out through a drainage field ( épandage). The system needs primary and secondary ventilation, and if the fosse is sited away from the house a grease trap ( bac à graisse) is put in between the house and the fosse. Drainage work is done by ‘ terrassiers’, and you can search ‘ terrassier assainissement’ in yellow pages ( pagesjaunes.fr) to find local firms.
Installation costs vary according to the size of the property, boundaries, access and the sub-soil. For three- to five-bedroom houses, I’ve seen bills from €6,500-€10,000; difficult sites or larger properties will cost more. You are going to need someone bilingual to help you through the system, preferably someone with knowledge of the process.
Mairies delegate drainage approvals to specialist agencies, usually called SPANC. Applications are made to SPANC, with details of the property and the proposal. They visit the site and work out what size of installation and in particular what type of post- fosse drainage field would be suitable. Soil tests may be required. Your terrassier quotes accordingly and good firms will also take charge of the application process. SPANC inspect during and at the end of the works before issuing a conformity certificate. SPANC fees vary across the country.
In Dordogne, you can find out about which SPANC covers your communauté de communes area by visiting the site: dordogne.fr/assainissement_non_collectif/ vous_etes_un_usager/694-1.
Each communauté (group of communes) has its own website, with a section on ‘ assainissement’, where you’ll find the application forms, details of local offices and often lists of approved firms.