|
The average household uses 175 liters per person per day, with average 4 persons per household.
175 l/p*d x 4 p x 30 d = 21,000 m3
This equals 21 cubic meters monthly per household. The state water agency* charges
US$ 8.50 for 21 cubic meters/month for sewage**
The neighborhood of Nova Cidade, which is served by the wastewater recycling facility, has approx. 200 households so:
$ 8.50 x 200 x 12 months = $ 20,400 annually
Local agencies calculate that half of these fees support maintenance and capital amortization costs of the collection system, with the other half going to operating costs for facilities.
Thus approx. US$ 10,000 annually is available for amortization and operating costs of a wastewater recycling facility.
(*NOTE: Source: Sabesp Grupo Tarifario 3 Categoria Residential Vigencia 15/07/96 - Financial statistics are used from Brazil's largest wastewater state agency, Sabesp in the adjoining state, as the local water agency at Silva Jardim has unreliable statistics.)
**NOTE: This calculation understates possible revenues. A large house in Silva Jardim pays a flat water/sewage rate of approx. $80 monthly, and a small house pays $20 to the local water agency. Source - Interview with administrator of Silva Jardim November 26, 1997. Therefore, the Sabesb-quoted figures for this calculation are at the very low end of the revenue scale.
|
|
