Agglomeration of Pariswaste water management

From a hygienist issue to an environmental goal

Sanitation in Paris agglomeration in 19th and earlier 20th century

• Many issues due to non correct sanitation (pollution of River and soil, cholera epidemics)

Sanitation in Paris agglomeration in 19th and earlier 20th century

The answer = hygienic and ecologic approach•

All into the sewage

1810

Expansion of the sewage network to lead the water to land treatment

1869

Seine aval : 6 000 T

Seine aval : 600 000 m3

Marne Aval : 35 000 m3

Grésillons : 100 000 m3

La Morée : 50 000 m3

Seine aval : 1 900 000 m3

Seine centre : 240 000 m3

Staff : 1600 S: 2000 km2

Population : 8 500 000 inhabitants

3 000 000 m3/day

A public company

Financials aspects

1. 102 Billions of Euro for 2005

Outcomes :

553 millions for immobilisation 410 millions for the sewage and treatment plan operation 139 millions for taxes, credits…

Incomes :

300 millions of fees from users (inhabitants and industries) 230 millions of subvention (AESN, Regional Authorities…) 315 millions of bank loan 170 millions writing off (amortization) 87 millions from other

Tax fee : 0,6017 €/m3 in 2006

The Future

Several challenges• Improvement of the treatment plants for N

and P• Stock and treatment of rain water with a

return period of 6 months• Limitation and monitoring rain water runoff

from new urbanization zone• Change sludge into a fertilizing product• Estimated Cost : 2 500 M€

The most important gains• No more cholera epidemic• Less impact in North Sea, because of the flows reduction of

P and N • No more fish mortality after big storms (500 T in the 90’s)• Better quality of the River Seine NH4

+ always < 0,5 mg/l and conform to use it to make drinking water

• more recreation activities : 3 species of fish in 1960 in the River Seine, 29 today ; rowing