Assessment of Inland Water Quality in Banjar Regency Using Remotely Sensed Satellite Image
Assessment of Inland Water Quality in Banjar Regency Using Remotely Sensed Satellite Image
ISSN No:-2456-2165
Abstract:- The main environmental issues in Banjar is compared to 2018, from 97 rivers in Indonesia, 67 rivers
Regency Indonesia are the handling of residential are lightly polluted, 5 rivers are lightly polluted and 25 rivers
wastewater and environmental degradation due to are lightly polluted and heavily polluted [1].
mining activities. Efforts to monitor and analyze water
quality status with a large area and diverse land use Banjar Regency is one of the areas in South Kalimantan
require a lot of time and money. This research will help which has a large river, namely the Martapura River with an
provide alternative solutions for predicting the quality of area of 453.88 km2, and a length of 36,566 meters [2]. Banjar
inland waters using remote sensing satellite image Regency itself has an area of 4,668.50 km2 with a potential
interpretation. The research was conducted to obtain the dry land area of 13,757 ha, tidal 32,252 ha, rainfed rice fields
distribution pattern of water quality parameters such as 13,446 ha, irrigation 5,497 ha, swamp or lebak 8,538 ha, and
Turbidity, TSS (Total Suspended Solid), organic CDOM non-rice field agricultural land covering an area of 320,602
(Colored Dissolved Organic Matter Absorption), and ha. In addition to strategic utilization in the agricultural
Chlorophyll-a (Chl-a). These four parameters are sector, the development of residential areas is also a strategic
generally monitored through field sampling which is issue of the Banjar Regency with one of the main problems,
time-consuming and costly. Remote sensing provides the namely the handling of residential wastewater disposal, and
possibility to provide water quality information over a environmental degradation due to mining activities [3]. The
wide area and identify trends in changing water quality Environmental Service of South Kalimantan Province noted
patterns through historical data. The research was that there are dozens of companies operating in the Martapura
conducted through the interpretation of Sentinel-2 sub-watershed area, three of which are coal mining
satellite imagery and other sources such as Landsat and companies. The existence of these dozens of companies has
SRTM. Data were collected over the last 5 years and the potential to trigger pollution of the Martapura river which
processed using the GEE (Google Earth Engine), ESA- is the source of PDAM's raw water, transportation,
SNAP (European Space Agency - Sentinel Application agriculture and fisheries as well as other community
Platform), and QGIS applications. The interpretation economic activities. In addition to coal mining, dozens of
results for current conditions are calibrated using field companies operating along the Martapura sub-watershed are
measurement data, then mapped to display patterns of plantations, rubber, plywood, shrimp freezing, hotel and
water quality parameter conditions spatially and home industries. Pollution of the Martapura River is a priority
temporally. The last step is to perform spatial statistical for the handling of the South Kalimantan Provincial
analysis and the trend of changes in water quality using Government [4].
the GEODA application. The distribution of water
quality parameter values shows various patterns for Efforts to monitor and analyze the status of water
inland waters in Banjar Regency but tends to increase in quality with a large area and quite diverse land uses require a
locations close to residential and agricultural areas. All large amount of time and money. This research will help
water quality parameters reviewed also show an provide alternative solutions for predicting the quality of
increasing trend in the last 5 years according to the inland waters using remote sensing satellite image
analysis period. interpretation. It is necessary to conduct research to obtain the
distribution pattern of water quality on the parameters of
Keywords:- Banjar Regency, Inland Water, Remote Sensing, turbidity (Turbidity), TSS (Total Suspended Solid), organic
Water Quality, Sentinel-2. CDOM (Coloured Dissolved Organic Matter Absorption),
and Chlorophyll-a (Chl-a). These four indicators are
I. INTRODUCTION generally monitored through field sampling which is time-
consuming and costly. Remote sensing provides the
The condition of inland water quality, based on data possibility to provide water quality information over a wide
from the Ministry of Environment and Forestry in 2019 stated area, and identify trends in changing water quality patterns
that the quality of river water in Indonesia is deteriorating through historical data. Remote sensing applications in
every year. Of the 98 rivers in Indonesia, 54 rivers are lightly waters have been used as an effective alternative to monitor
polluted, 6 rivers are lightly polluted-moderately polluted, water quality. The color of the waters captured by remote
and 38 rivers are lightly polluted-severely polluted. This data sensing applications provides information about the optical
II. METHOD
Phosphate parameters at some points exceed the Based on the resulting image, the existing bands are
national water quality standard [7]. High levels of phosphate then processed to obtain the values of NDWI (Normalized
are generally caused by human or animal waste, and domestic Difference Water Index), NDTI (Normalized Difference
activities. Excessive phosphate concentration will increase Turbidity Index), Turbidity, TSS (Total Suspended Solid),
the growth of algae which results in reduced sunlight entering CDOM (Coloured Dissolved Organic Matter), and Chl-a
the water bodies [8]. BOD (Biological Oxygen Demand) (Chlorophyll-a).
parameter exceeds the national water quality standard for all
measurement points. The higher the BOD level, the higher C. River Water Quality Profile
the activity of organisms to decompose organic matter. COD The profile line in Fig. 3 is determined along the axis of
(Chemical Oxygen Demand) content showed a higher value the Martapura river with a total length of about 120 km. This
than the national water quality standard at certain locations of profile is used to provide an overview of the pattern of
the swamp. Similar to BOD, COD levels in water are changes in water quality parameters along the Martapura
associated with a decrease in dissolved oxygen content in the River from upstream to downstream.
waters [9]. TSS (Total Suspended Solid) level at point river 3
also exceeded the national water quality standard limit.
domestic and agricultural activities show a large influence on
water quality conditions at the sampling points.
B. Satellite Imagery
The satellite image is taken from the Sentinel-2 satellite
data with the help of the Google Earth Engine script. The
image obtained through this script then goes through the
stages of converting the coordinate reference system to UTM
coordinates (WGS84/UTM Zone 50S). The image is also
resampled to a resolution of 10 m. The images obtained are
satellite images for Bands 1 to 12 which are averaged per year
of observation. The image obtained is still divided into
several images, so it must undergo a merging process. The
merging process is carried out with the SNAP application
through mosaicking. The combined satellite images are then
processed and displayed in the SNAP application (Fig. 2).
Fig 3:- River profile line
Observations were made from early 2018 to mid-September
2022.
The results of satellite image processing along the river
profile line (Fig. 4) showed a more varied pattern of
fluctuations in the turbidity, TSS, and Chl-a parameters
upstream. The CDOM parameter is very volatile along the
Martapura river in 2018. CDOM shows an increase in
locations close to residential and agricultural areas. In 2019
the pattern of changes that occur along the river profile is still
fluctuating, especially for TSS and CDOM parameters. The
turbidity parameter still has a higher tendency in the upstream
area, and the CHL-a parameter is relatively not subject to
various fluctuations. Conditions in 2020 compared to the
previous year experienced an increase in TSS, CDOM, and
Fig 2:- RGB image from SNAP Chl-a concentration.
IV. CONCLUSION
ACKNOWLEDGMENT
REFERENCES