W. J. Baumol, Ramsey pricing, pp.49-51, 1987.
DOI : 10.1057/9780230226203.3383

J. J. Boland and D. Whittington, The political economy of water tariff design in developing countries: Increasing block tariffs versus uniform price with rebate. In The political economy of water pricing reforms, pp.215-235, 2000.

S. Brown and D. Sibley, The Theory of Public Utility Pricing, 1986.
DOI : 10.1017/CBO9780511666773

G. Burtless and J. Hausman, The Effect of Taxation on Labor Supply: Evaluating the Gary Negative Income Tax Experiment, Journal of Political Economy, vol.86, issue.6, pp.1103-1130, 1978.
DOI : 10.1086/260730

D. Chicoine, S. Deller, and G. Ramamurthy, Water Demand Estimation Under Block Rate Pricing: A Simultaneous Equation Approach, Water Resources Research, vol.42, issue.6, pp.859-863, 1986.
DOI : 10.2307/1056769

B. Collignon, Urban Water Supply Innovations in Côte d'lvoire: How Cross- Subsidies Help the Poor. Nairobi: Water and Sanitation Program -Africa, 2002.

B. Collignon, R. Taisne, and J. S. Kouadio, Water and Sanitation for the Urban Poor in Côte d'Ivoire. Nairobi: Water and Sanitation Program -Africa, 2000.

L. Corral, A. Fischer, and N. Hatch, Price and Non-Price Influences on Water Conservation: An Econometric Model of Aggregate Demand under Non Linear Budget Constraint. Working Paper No 881, 1998.

D. Diakité and A. Thomas, Structure des Coûts d'Alimentation en Eau Potable : Une Application aux Données des Centres de Production Ivoiriens, 2005.

D. Diakité and A. Thomas, La Demande d'Eaù a Usage Résidentiel en Côte d'Ivoire : Une Analyse Econométrique sur Données de Panel, 2006.

S. Garcia and A. Reynaud, Estimating the benefits of efficient water pricing in France, Resource and Energy Economics, vol.26, issue.1, pp.1-25, 2004.
DOI : 10.1016/j.reseneeco.2003.05.001

P. H. Gleick, Basic Water Requirements for Human Activities: Meeting Basic Needs, Water International, vol.3, issue.2, pp.83-92, 1996.
DOI : 10.1080/02508069108686108

A. Gomez-lobo and D. Contreras, Water Subsidy Policies: A Comparison of the Chilean and Colombian Schemes, The World Bank Economic Review, vol.17, issue.3, pp.391-407, 2000.
DOI : 10.1093/wber/lhg028

J. A. Hausman, Exact Consumer's Surplus and Deadweight Loss, American Economic Review, vol.71, pp.662-676, 1981.
DOI : 10.2307/2171777
URL : http://dspace.mit.edu/bitstream/1721.1/50211/1/35721008.pdf

J. Hewitt and W. Hanemann, A Discrete/Continuous Choice Approach to Residential Water Demand under Block Rate Pricing, Land Economics, vol.71, issue.2, pp.173-192, 1995.
DOI : 10.2307/3146499

J. J. Laffont, Competition Information and Development, Annual World Bank Conference on Development Economics, 1998.

J. J. Laffont, Regulation, Privatisation and Incentives in Developing Countries, Current Issues in Economic Development, 1996.

J. J. Laffont and J. Tirole, Competition on telecommunications, 2000.

J. Laffont and J. Tirole, A Theory of Incentives in Procurement and Regulation, 1993.

R. Martinez-espiñeira, Estimating Water Demand under Increasing-Block Tariffs Using Aggregate Data and Proportions of Users per Block, Environmental and Resource Economics, vol.26, pp.5-23, 2003.
DOI : 10.1007/978-94-015-9984-9_2

C. Ménard and G. Clarke, Reforming Water Supply in Abidjan, C??te d'Ivoire, Working paper Series, vol.2377, 2000.
DOI : 10.1016/B978-008044077-4/50010-7

R. Moffitt, The Econometrics of Piecewise-Linear Budget Constraints, Journal of Business & Economic Statistics, vol.14, issue.3, pp.317-328, 1986.
DOI : 10.1016/0047-2727(80)90042-0

R. Moffitt, The Econometrics of Kinked Budget Constraints, Journal of Economic Perspectives, vol.4, issue.2, pp.119-139, 1990.
DOI : 10.1257/jep.4.2.119

J. Nordin, A Proposed Modification of Taylor's Demand Analysis: Comment, The Bell Journal of Economics, vol.7, issue.2, pp.719-721, 1976.
DOI : 10.2307/3003285

J. E. Prieger, Ramsey pricing and competition: The consequences of myopic regulation, Journal of Regulatory Economics, vol.4, issue.1, pp.307-321, 1996.
DOI : 10.1007/BF00157675

S. Renzetti and J. Kushner, Full Cost Accounting for Water Supply and Sewage Treatment: Concepts and Case Application, Canadian Water Resources Journal, vol.69, issue.3, pp.13-22, 2004.
DOI : 10.2307/1925527

S. Renzetti, An empirical perspective on water pricing reforms In The political economy of water pricing reforms, pp.123-140, 2000.

S. Renzetti, Evaluating the welfare effects of reforming municipal water prices, Journal of Environmental Economics and Management, vol.22, issue.2, pp.147-192, 1992.
DOI : 10.1016/0095-0696(92)90011-K

J. Shefter and E. David, Estimating Residential Water Demand Under Multipart Tariffs Using Aggregate Data, Land Economics, vol.61, pp.21-33, 1985.

J. Strand and I. Walker, Water markets and demand in Central American cities, Environment and Development Economics, vol.10, issue.3, pp.313-335, 2005.
DOI : 10.1017/S1355770X05002093

S. Swallow and C. Martin, Long run price inflexibility and efficiency loss for municipal water supply, Journal of Environmental Economics and Management, vol.15, issue.2, pp.233-247, 1988.
DOI : 10.1016/0095-0696(88)90021-6

R. Willig, Consumer Surplus without Apology, American Economic Review, vol.66, pp.589-597, 1976.

R. Wilson, Nonlinear Pricing, p.47, 1993.

, 67 -1.30 -2.41 -2, Basse Cote 22

. Abidjan-north,

. Abidjan-south,

. Notes, Average income is in 1,000 USD per year. Tk stands for Tariff k

. Min, q min (in m 3 ) denote the marginal price and the upper bound of the simulated social block respectively. W Loss (in USD/year) is the (negative) welfare change for a representative poor household. BillEq (in USD/year) denotes the bill a poor household would pay for a volume corresponding to the (optimal)