Tanjung Gunung, Pangkalan Baru District, Central Bangka Regency is an area that is included in the Special Economic Zone. The Development of this area will have an impact on the increasing demand for water that must be provided by the management. The water resources will be supplied from Kolong Kebintik. Other than supply to the Special Economic Zone, it is also planned to supply water in Pangkalan Baru District. The water demand for Special Economic Zone is 43 l/s and water demand for the Pangkalan Baru Disctric is 48.11 l/s. So the total domestic demand is 91.11 l/s. To guarantee water in Kolong Kebintik is still available to needs of the Special Economic Zone and Pangkalan Baru District, it is necessary to analyze the reliability using standard operating rule. If want to get 100% reliability of Kolong Kebintik, then use only 22.8 l/s of the total demand 43 l/s or only 53% of the needs of the Special Economic Zone.

East Belitung Regency is one of the regencies located on Belitung Island. East Belitung Regency has a tropical and wet climate with a fairly high variation of rainfall. Rainfall forecasting is an important thing to model because of the many uses of rainfall forecasting results such as irrigation planning, flood prediction, erosion prediction and others. This study aims to predict rainfall for the next 5 years by using a time series model by reviewing the heteroscedasticity of the data. From the results of the analysis of rainfall in East Belitung Regency with a seasonal pattern. The best model used is ARIMA (0, l, l)(2, l, l)12 with insignificant heteroscedasticity.

Kulong formed from tin mining activities has the potential as a source of water. Kulong in Beluluk Village, Pangkalan Baru District, which can be used as a water source is Kulong Krasak. The use of the kulong as a water source is not only seen from the ability of the kulong to meet the water needs of the community but also must maintain its sustainability. The reliability analysis of the kulong is a way to find out the amount of water release that is allowed so that the sustainability of the kulong is maintained. To determine the availability of Kulong Krasak water for the next 16 years, a prediction of water availability is made, namely from 2022 to 2037. From the results of the analysis, it was found that the water demand in Beluluk Village in 2037 was 7.86 l/s. The maximum water availability occurs in April, which is 20.43 l/s and the minimum occurs in September, which is 6.57 l/s. The results of the standard operating rule analysis show that Kulong Krasak has 100% reliability if the release target is 5.61 l/s of the total water demand, which is 7.86 l/s.

The Province of the Bangka Belitung Islands as one of the provinces in the form of an archipelago has a number of islands that have the potential to be developed, including Bangka Island. The coastal areas on Bangka Island have similar environmental conditions, namely environmental problems due to illegal tin mining. However, the environmental conditions in each of these coastal areas have not been well mapped. Therefore, this study aims to map the environmental conditions in the coastal area of Bangka Island. This study uses a qualitative approach by describing the environmental conditions of the coastal area on the island of Bangka in-detail and in-depth. In addition, this research also communicates directly with informants or officers at the Marine and Fisheries Service and village government officials in the coastal area in question to explore in-depth information. Furthermore, this research data was also obtained from direct observation at the location of the coastal area on the island of Bangka. Through this approach, it is hoped that an overview and understanding of the environmental conditions in coastal areas on Bangka Island can be obtained and how to manage and utilize the potential that has been carried out to improve environmental quality.