Is tenant responsible for water and sewage maintenace?

It's all in the lease. Whatever the lease says stands.

The answer to your question will be governed by the terms of your lease contract. A landlord must provide a habitable space which meets minimum standards for habitability. Heat and hot water systems must be in place, though the landlord need not provide the utilities to use them free of charge. Things like garbage removal where municipalities do not provide the service will be determined by the lease. The duty may be explicit or it may be covered by some form of cleanliness clause. Water and sewage are traditionally handled by the landlord, but this is not required. Maintenance and improvement are usually the landlord's responsibility, but the duties can be assigned to the tenant by the lease. You should consult with a landlord-tenant attorney if your lease is not clear on these points or if you are having a disagreement with your landlord/tenant.