The development of the water supply system in Kotor has occurred in several phases:
The first water supply system of Kotor was built during the Austro-Hungarian monarchy, when the upper Grbalj springs were captured and water was brought to the reservoir in Škaljari (old Škaljari reservoir V=350 m3, Kd=80 mnm), from where it was distributed to consumers.
In Risan, around 1940, the Smokovac spring was captured, and a reservoir (V=120 m3, Kd=100 mnm) was built. Although this reservoir has insufficient capacity, it is still in use, but the Smokovac spring (most likely due to the earthquake) reduced its yield and is no longer used for water supply.
In the 1960s, the Tabačina and Spila pumping stations were built, which have not significantly changed in the construction part to this day. With the construction of the Tabačina pumping station, water supply was enabled for buildings in the area from the Old Town to Orahovac, and from Škaljari to Stoliv. During that period, the Mečerov Brijeg reservoir (Dobrota I) was built, along with five reservoirs in the Muo-Prčanj-Stoliv area. A larger pipeline was also built from the Upper Grbalj springs to the Škaljari reservoir, allowing gravity-fed delivery of a larger amount of water to consumers.
After the earthquake, the Škaljari reservoir (new reservoir V=2000 m3, Kd=74 mnm) was built, with a pumping station that pumps water via Trojica to the Stara Fortica reservoir. A complete distribution network was built in the industrial zone, and the Stara Fortica reservoir (V=1000 m3, Kd=91 mnm). Two more reservoirs (Dobrota II and Dobrota III) were built for the newly constructed buildings in Dobrota. Pipelines were built from Stoliv to Risan (underwater pipeline Verige) and from Orahovac to Risan, forming a “ring” around the bay.
Since the Škurda spring regularly becomes salty during the summer, the Orahovac springs Ercegovina and Cicanova kuća were captured and included in the water supply system in 1988.
The construction of the Vrmac tunnel in the early 1990s revealed a water source that represents exceptional value due to its proximity to the city and favorable altitude (lower exploitation costs).
In recent years, a new pressure pipeline from Škaljari to Trojica, the Trojica reservoir, a new pipeline from Orahovac to Perast to Risan, and the replacement of the DN400 pipeline in the Vrmac tunnel (connection to the regional water supply) have been constructed, and the Tunnel pumping station was built.
The regional water supply system was put into operation in 2010, and since then, water supply during the summer period has been uninterrupted.
Water Sources
The Škurda spring is the largest spring, and it supplies water to the settlements along the route Škaljari – Dobrota – Risan. It is located almost at sea level, which causes water salinization during the summer period. The minimum yield of the spring is over 300 l/s.
The Ercegovina and Cicanova Kuća springs in Orahovac are naturally connected to the Škurda spring. In winter, during precipitation, this spring has drinking water, but its yield decreases at the beginning of summer, and salinization occurs. When the Škurda spring experiences salinization, these springs provide a maximum summer yield of over 200 l/s of drinking water and become the main source.
The spring in the Vrmac tunnel is located at around 57 meters above sea level and does not experience salinization. Its yield is around 100 l/s in winter, but it decreases to a minimum of 10 l/s in the summer period. The Upper Grbalj springs are located at elevations above 360 meters. There are four smaller springs (captures: Ponikva, Maroš, Ubao, and Podskala). The yield of these springs ranges from 80 l/s to about 7 l/s at the minimum. The Simiš spring also has variable yield. It has a higher yield in winter, but only a maximum of 40 l/s is captured, while the yield in the summer drops to 3 l/s.
The Spila spring occasionally dries up, and during the summer, the water regularly becomes saline. Around 40 l/s is captured, and it is used to supply Risan.
Operation of the Water Supply System
Since 2010, when the regional water supply system was put into operation, no restrictions have been imposed on water supply in Kotor. In the winter period, the main source of the Kotor water supply system is the Škurda spring in Tabačina, and the Vrmac tunnel spring and the Upper Grbalj springs are also in use. During the summer period, usually in mid-summer, water salinization regularly occurs at the Škurda spring in Tabačina, when a significant amount of drinking water appears in the Orahovac springs. At that time, the water supply is sourced from the Orahovac springs, making them the main sources for supplying Kotor.
A common feature of almost all the sources in the Kotor system is the large difference in the available amounts of drinking water between winter and summer. The yield of the springs in the winter period exceeds the water demand, while in the summer period (when water demand is highest), the yield depends on the hydrological conditions. Water salinization regularly occurs at the Škurda and Spila springs, and the yield of other springs decreases, which previously led to the imposition of restrictions. With the activation of the Regional Water Supply, the insufficient quantities of drinking water in the summer period have been secured.
The water quality in all Kotor springs is good, so, except for chlorination, no additional water treatment is required. The exception is the regular salinization of the water in the summer period. Salinization can also occur in the winter period due to a small amount of precipitation (e.g., December 2004).
The problem of the Kotor Water Supply is the outdated water supply network and the poor quality of pipe materials (AC, PVC).
WATER SUPPLY NETWORK
Kotor’s water supply system has 146 km of primary network and over 200 km of secondary network. The largest diameter of the pipeline is 400 mm, and the materials used include PVC, PE, AC, steel, and ductile iron. There are about 11,000 consumers in the household category and about 800 in the legal entity category.
Management
Đuro Marković
Executive Director