The traditional methods of funding physical infrastructure - roads, public transport, water, sewerage, drainage, electricity, gas, telephones and garbage disposal - have involved varying combinations of loans amortised from current revenue, property taxes, user charges, access charges, developer charges, fuel taxes and subsidies from general tax revenue. These methods of funding have come under pressure in recent years for a number of reasons: shortages of government capital funds, pressures to reduce taxes, and attempts to make the funding systems more equitable and to use it to increase efficiency in the supply of these services and to reduce their adverse effects on the environment.