THE Housing Authority, which has billions of dollars in reserves, has dropped plans to improve security on its estates after residents refused to contribute towards the costs. Legislative Councillor the Reverend Fung Chi-wood said the authority was ignoring the basic responsibility to safeguard tenants. A series of rapes on public housing estates sparked calls for better security six months ago, but improvements are unlikely before next year because of the dispute over who should pay. The authority had planned trial security measures on two Tsing Yi estates, but postponed them because residents were unable or unwilling to pay the $60 per household per month towards the costs. The Lift and Escalator Contractors Association has estimated that security measures, including gates and cameras, in the territory's 1,700 rental estates would cost a few hundred million dollars. However, the Housing Authority budget shows it could have a balance as high as $15 billion by March - the end of the 1993-94 financial year. Mr Fung, who is a Legco housing panel member, called on the authority to immediately upgrade security because ''it is a basic need and the Government's responsibility to safeguard people''. He added: ''With the cash reserves the authority has, there is no reason they could not upgrade security facilities at once. It seems to be a problem of heart.'' A Housing Authority spokesman said the billions of dollars of cash from tenants' deposits, constructors' deposits, and first instalment payments from Home Ownership Scheme buyers had been invested to raise money to build more housing. However, Mr Fung believes the money is not being used effectively if it is invested at the expense of basic safety. ''It is unfair not to protect the people who live there. Outside their door is a public place by law and by practice, but police don't patrol the corridors.'' He said the Government had failed to consider the security aspect of the new housing estates. ''Having so many flats in some buildings increases the chances of crime, but there are also more entrances and long corridors, and other dark places on the estates.'' Mr Fung said a small part of the funds could provide basics such as security gates and close-circuit television, and residents could top up the measures if they wished by paying for security guards. Lee Yan-chuen, the head of the Housing Authority working group formed a month ago to prepare costing on options, said the authority had been forced to call off security trials planned for two Tsing Yi housing estates because residents refused to contribute toward costs. ''Residents said they would not pay so the trial was set aside,'' he said. The working group is compiling a report on options, including ones it could finance itself, he said. The report will be ready late this year or early next year, but improvements may not be implemented for some time. Free trials would be held at Tin Shui and Yiu Tung estates early next year before any improvements were made across the board, and any improvements would be subject to manpower, he said. The Housing Authority has committed itself to implementing the $2 billion Central Control Monitoring System in the next two to three years. The pilot for the monitoring system project, which will use computer devices within estates so headquarters can check service standards and performance, was completed last year.