You’ll find firms in Huélago, Dúrcal, Baza and Loja, among other towns. Within 20 km of Granada is Desatascos Ruiz Granada. For work that needs return visits, a firm within an hour’s drive is usually worth a slightly higher quote.
Desatascos Sierra Nevada and Desatranques Costa Tropical lead on Google among firms with at least 20 reviews. The average rating across the list is 4.4 (firms with at least five reviews). A handful of five-star reviews is a start, but ask for a job you can go and see.
A septic tank and a treatment plant are different things with different upkeep. Ask which suits your plot and soil, what the price includes from digging to commissioning, and how often it will need emptying.
Questions to ask before you sign
- Septic tank or treatment plant: which suits my plot, and why?
- Has the soil been tested?
- What does the price include, from digging to commissioning?
- How often will it need emptying, and do you do that?