Reliable supply and quality water in every household
Water Supply
The current water supply system operated by Vodovod zapadne Slavonije d.o.o. was formed through the merger of the companies Slavča d.o.o. and Regionalni vodovod Davor d.o.o. In the 1970s, an embankment dam and the Bačica reservoir were constructed. The reservoir was originally intended for technological purposes, but since the mid-1990s it has been used to supply the town and surrounding settlements with drinking water.
In addition to the reservoir, part of the water that is treated and distributed to the town is sourced from the Šumetlica stream at a water intake structure located in the Strmac area.
The main components of the existing water supply system include:
- water intakes from the Bačica reservoir and Šumetlica stream,
- a drinking water conditioning facility,
- a clean water storage tank,
- a transport pipeline to the settlements,
- and the water distribution network within the settlements.
Core Activities of the Water Supply System
- Supply of drinking water (abstraction, purification, and distribution to consumers)
- Installation of household connections to the network
- Maintenance of the existing network (repairing bursts and replacing worn-out parts)
- Construction of new supply pipelines
- Replacement and calibration of water meters
In addition to the pipeline network serving the City of Nova Gradiška, the system also maintains the pipeline that supplies the municipality of Davor, as well as the settlements of Stara Gradiška, Uskoci, Gornji Varoš, Donji Varoš, and Novi Varoš. The water is drawn from wells using pumps and transported to a water tower that ensures the necessary pressure in the network. This facility is equipped with all the necessary water conditioning systems.
The existing water supply systems managed by Vodovod zapadne Slavonije d.o.o. provide drinking water to the population in the following areas:
- City of Nova Gradiška
- Municipality of Cernik
- Municipality of Davor
- Municipality of Rešetari
- Municipality of Dragalić
- Municipality of Gornji Bogićevci
- Municipality of Stara Gradiška
- Municipality of Okučani
- Municipality of Nova Kapela
- Municipality of Staro Petrovo Selo
- Municipality of Vrbje
Water sources used for supply:
- Bačica accumulation lake
- Šumetlica cascade – Strmac
- Davor
Bačica Accumulation Lake
The dam and reservoir “Bačica” are located on the southern slopes of Mount Psunj, northwest of Nova Gradiška, near the settlements of Cernik, Giletinci, and Cernička Šagovina. It was constructed with the aim of protecting against the harmful effects of torrential floodwaters from the hills and serves as a retention basin for the broader catchment area north of Cernik. The catchment area of the reservoir covers 8.3 km², while the reservoir itself occupies an area of 20.2 hectares. The dam’s structural height is 17 meters, and its capacity is 1,280,000 cubic meters.
Following the construction of the water conditioning facility, the use of the stored water for public water supply became possible. It was later determined that the Bačica reservoir alone could not meet the growing demand for water. Additional water volumes were secured by capturing surface water from the Šumetlica stream and constructing a connecting pipeline between Šumetlica and Bačica.
According to the Decision on the Register of First-Order Waters, the Bačica reservoir is classified as a retention basin of major significance, either for flood protection or due to its volume exceeding 500,000 m³.
The Šumetlica stream is classified as a high-energy torrential watercourse. First-order waters include surface and groundwater sources that can be used for drinking or food industry purposes either naturally or after treatment, as well as surface waters suitable for the cultivation of noble fish species.
Water Supply to the Conditioning Plant
Water is supplied to the conditioning plant from the “Bačica” accumulation and/or the water intake from the Šumetlica stream. Water from the accumulation requires full treatment to make it suitable for drinking, while water from Šumetlica is of better quality but, depending on hydrological conditions, is either directed to treatment or to the accumulation (for example, when color and turbidity are high due to heavy rainfall, snowmelt, forestry work, etc.).
The existing water conditioning plant was built in 1980 with a capacity of Q = 75 l/s. In 1994, a lamellar sedimentation tank (Q = 2×40 l/s) was constructed to replace the war-damaged accelerator-type clarifier, which was never restored. Water reaches the plant via a supply pipeline, where it first undergoes pre-chlorination with liquid chlorine dioxide. It is then directed to the lamellar sedimentation tank, where flocculation and coagulation occur using aluminum sulfate and polyelectrolyte. Activated carbon and potassium permanganate are added as needed.
The next treatment stage includes rapid sand filters filled with quartz sand, followed by final disinfection with sodium hypochlorite. The treated water is then stored in the so-called clean water reservoir before being distributed to users. A key issue with the plant is outdated technology, which, given increased water demand and surface water instability, cannot always ensure the required drinking water quality. Compared to 30 years ago, when the plant was built, water flow has significantly increased, leaving insufficient contact time with the treatment chemicals. For this reason, reconstruction and improvements in treatment quality were planned in cooperation with Croatian Waters and EU funds for the year 2015.
Water quality testing at the source, and health compliance checks at water supply facilities and within the distribution network, are conducted by the Public Health Institute of Brod-Posavina County.
In cases where analytical reports show that water quality does not meet legally prescribed values, consumers are informed via public announcements on the local radio station and the website – vzs.hr.
In addition to water treatment and supply, the company also installs connections to the network for end users, maintains the existing infrastructure (repairing leaks and replacing outdated parts), and builds new supply pipelines. Water meters are regularly replaced within legally defined intervals and sent for calibration to authorized companies. Water consumption is recorded monthly by meter readers. Consumers are required to allow the water service provider unrestricted and continuous access to the water meter without delay or hindrance.
In the future, the company aims to identify new water sources, protect and maintain existing ones, and expand the water supply network to new areas. All of these efforts aim to ensure sufficient quantities of safe drinking water, improve service quality, and increase customer satisfaction.
Sewage System
Wastewater is the used and discarded water from settlements and production. All wastewater, including sanitary water, industrial and craft wastewater, ends up in the public sewage system.
The sewage system for wastewater and stormwater is designed as a joint system for the city of Nova Gradiška and the settlements of the municipalities of Rešetari and Cernik. The majority of the system is designed as a combined system, with a smaller portion as an incomplete separate system. Most of the retention basins and stormwater overflows have been built, and soon the necessary equipment for the system will be designed, improving its functionality. All of this needs to be constructed and installed before the construction of the actual wastewater treatment plant.
The recipient for wastewater is the lateral channel, which flows into the Šumetlica stream south of Nova Gradiška. The construction of the sewage system began in the late 1970s with the construction of the collector, some stormwater overflows, and retention basins, followed by other secondary pipelines with household connections.
Due to the terrain configuration in the north-south direction within the city area, only two pumping stations are currently required, and the majority of the sewage system operates by gravity. However, the parts of the settlement of Rešetari that are being constructed now and those in the design phase will require a significantly larger number of pumping stations to transport wastewater to the future treatment plant, making the system more complex and expensive to maintain.
The plan also includes the arrangement of the southern part of the city, which consists of the settlement of Ljupina. This area will be resolved independently of the wastewater treatment plant of the city. Other settlements are at various stages of development, as well as in terms of system maintenance.
The sewage area includes the following activities:
- Wastewater treatment for the public sewage system
- Maintenance of the public sewage system
- Maintenance and emptying of septic tanks in and outside the city area
- Design of sewage connections
- Services for unblocking and flushing internal sewage systems
- Construction of secondary pipes and collectors with associated facilities
- Solving problems with existing collecting pipes where connection to the sewage system is not possible
- Through wastewater treatment, the quality of the discharged water into the recipient must be the same or higher than that of the watercourse itself.
The wastewater sewage system is one of the essential conditions for the normal life of people, as well as for the protection of plant and animal life, and thus the environment in general.