Information from the Statistics and Census Service (DSEC) indicated that total land area of Macao measured 29.5 km2 at the end of 2009, up by 1.0% year-on-year; however, the population registered negative growth as a consequence of a substantial decrease in non-resident workers, lowering the population density from 19,000 per km2 in 2008 to 18,000 per km2. Total lane length of public roads was 413.1 km, and the motor vehicle density was 460 vehicles per km. The Rua do Campo air quality monitoring station recorded 301 days of good air quality in 2009. However, the monitoring station at the Northern District, Big Taipa Hill and Rua do Campo registered 7 days, 3 days and 2 days respectively when the observed value of respirable suspended particulates exceeded the standard value. In 2009, the lowest pH value of rainwater was 3.8 (precipitation with pH value lower than 5.6 is classified as acid rain). The quality of potable water from the distribution network and Water Treatment Plants of Macao conformed to the standard according to the results of the analysis carried out by the Laboratory of the Civic and Municipal Affairs Bureau. The salinity level of potable water was classified as Low in 2009. The approval rate of water samples taken from the 10 public swimming pools ranged from 86% to 100%. In addition, water quality of the Hac Sa and Cheoc Van beaches was acceptable. Macau Waste Systems Company Limited (CSR) collected 160,000 tonnes of domestic garbage in 2009, down by 11.0% year-on-year; volume of garbage collected from the business sector rose by 16.5% year-on-year to 88,000 tonnes, whereas that of construction waste decreased by 19.2% to 1,567,000 m3. Moreover, 325,000 tonnes of garbage were processed in the Incineration Plant, an increase of 8.8% over 2008. As regards waste water treatment, the average capacity of waste water treated was 183,000 m3 per day. A total of 4,533 cases of noise complaints were reported in 2009, down by 2.3% year-on-year, mostly about noise from conversation and shouting, and disturbance from neighbours. With regard to educational activities on environmental protection, the Environmental Protection Bureau and the Civic and Municipal Affairs Bureau organized 525 promotional activities in 2009, with approximately 413,000 participants.
