1.2 Water Resources

1.2 Water resources

1.2.1. Status and issues

The Republic of Moldova is located in South-East of Europe, in a region with temperate climate and relatively limited humidity.

The hydrographic network includes 3621 rivers and rivulets (including 7 water courses exceeding 100 km length and 247 exceeding 10 km length), 57 lakes with a total area of 62.2 km2 and about 3000 ponds. The entire network of water courses exceeds 16,000 km. Moldova is mostly located between two large rivers: Dniester and Prut. River Dniester, with a basin covering 57% of the Moldavian territory and an average annual discharge of 10 km3, separates the Republic of Moldova from Ukraine. River Prut, with a catchment covering 24% of country’s territory and a yearly discharge of 2.4 km3, delimits Moldova from Romania. The largest natural lakes are situated in the lower part of rivers Prut and Dniester. The largest water reservoirs are Costesti-Stinca - on river Prut (735 million m3) and Dubasari - on river Dniester (490 million m3). The hydrographic and hydrologic characteristics of the main water courses and water bodies are given in tables 1.1 and 1.2 [30].

Table 1.1

The hydrographic and hydrologic characteristics of the main water courses

River / Length, km / Surface of hydrographic basin, km2 / Average annual discharge, million m3 / Average discharge,
m3/s
Dniester * / 1352 (657) ** / 721000 (19070)** / 10700 / 330
Prut * / 976 (695) ** / 27500 (7990) ** / 2906 / 92
Danube * / 2857 (1) ** / 817000 (8350)** / 203000 / 6500
Raut / 286 / 7760 / 313 / 9,9
Bic / 155 / 2150 / 91,3 / 2,9
Botna / 152 / 1540 / 33,6 / 1,1
Ichel / 101 / 814 / 20,5 / 0,7
Cubolta / 100 / 947 / 61,0 / 1,6
Ialpug * / 142 (135) ** / 3180 (3165)** / 91,2 / 2,9
Cogilnic * / 243 (125) ** / 3910 (1030)** / 59,1 / 1,9
Cainari / 113 / 835 / 46,8 / 1,4
Ciuhur / 97 / 724 / 21,8 / 0,7
Cahul * / 39 / 605 / 9,2 / 0,3

* Transboundary waters

** The length and catchment area of the rivers within the political boundaries of the Republic of Moldova are given in brackets

Table 1.2

The hydrographic and hydrologic characteristics of the main water bodies

Water body / River / Year of creation / Water volume,
million m3 / Water surface,
km2
Badragii Vechi / Racovat, Prut / 1989 / 4.9 / 1.0
Beleu (natural lake) / Prut / 2.1 / 6.26
Ghidighici / Bic / 1963 / 1.5 / 1.3
Bic (natural lake) / Bic / 40.0 / 8.0
Dubasari / Dniester / 1954 / 490.0 / 67.5
Cahul (natural lake) * / Danube / 240.0 / 99.2
Caplani / Caplani / 1983 / 8.3 / 1.5
Ceaga / Ceaga / 1960 / 4.1 / 2,8
Cneazevca / Sarata / 1967 / 2.8 / 1.0
Comrat / Ialpug / 1957 / 4.0 / 1.7
Congaz / Ialpug / 1961 / 9.9 / 4.9
Costesti / Botna / 1962 / 3.3 / 1.8
Costesti-Stinca** / Prut / 1976 / 735.0 / 59.0
Cuciurgan (natural lake) * / Cuciurgan-Nistru / 88.0 / 27.3
Ialoveni / Isnovat / 1978 / 21.7 / 4.4
Manta (natural lake) / Prut / 1.5 / 2.3
Mingir / Lapusna / 1982 / 12.2 / 2.6
Rezeni / Botna / 1963 / 3.4 / 1.9
Sarata Noua / Sarata / 1967 / 2.2 / 1.5
Taraclia / Ialpug / 1988 / 62.0 / 15.1
Ulmu / Botna / 1961 / 2.2 / 0.7
Zgurita / Cainari / 1980 / 1.7 / 0.9
Volontiri 1 / Bobei / 1957 / 1.6 / 0.8
Volontiri 2 / Bobei / 1988 / 12.0 / 1.9

* Cahul and Cuciurgan are international lakes (Ukraine).

** The Costesti - Stinca reservoir is operated jointly with Romania.

The river water resources are classified in 4 categories: natural resources, generated by the specific climatic conditions of the territory; real resources, collected from the entire river catchment, modified by human activity; ecological resources, necessary to maintain the ecologic balance of the river and available resources, which can be used for industrial, agricultural and household purposes. The distribution of water resources is shown in table 1.3 [37].

Table 1.3

The water resources of the Republic of Moldova, km3

Source / The category of water resources
Natural / Real / Ecolo
gical / Available
multi-annu
al average / availability / multi-annu
al average / availability / multi-annual average / availability
75% / 95% / 75% / 95% / 75% / 95%
Dniester river / 10,70 / 8,67 / 6,42 / 10,40 / 8,27 / 6,12 / 3,70 / 6,70 / 4,57 / 2,42
Prut river / 2,90 / 2,38 / 1,83 / 2,81 / 2,30 / 1,71 / 0,55 / 2,26 / 1,75 / 1,16
Small rivers of the Dniester and Prut basins / 1,14 / 0,65 / 0,35 / 1,08 / 0,58 / 0,31 / 0,31 / 0,77 / 0,27 / 0
Small rivers out of the Dniester and Prut basins / 0,08 / 0,04 / 0,02 / 0,07 / 0,04 / 0,02 / 0,02 / 0,05 / 0,02 / 0
Total / 14,82 / 11,74 / 8,62 / 14,36 / 11,19 / 8,16 / 4,58 / 9,78 / 6,61 / 3,58

Note: The available water resources of the Dniester and Prut rivers are proportionally distributed among Ukraine, Republic of Moldova and Romania [21].

The density of hydrographic network is, on average, 0.48 km/km2, varying from 0.84 km/km2 in the north of the country to 0.12 km/km2 in the east. The main feeding sources of rivers are rainfalls and snowmelt runoff. The hydrologic regime of the rivers reflects the climatic conditions specific to Moldova. On average, the annual runoff from the territory of Moldova (internal resources) is 1.32 km3 of water. The average precipitation rate in the north-western areas is 500-600 mm, decreasing gradually to 370-400 mm towards south-west.

Most precipitations during the year fall as rains and only 10% as snow. The rivers carry 40-50% of the annual discharge in spring time. In Dniester, 44% of the annual runoff is passed during spring, 26% in summer, 16% in autumn and 14% during winter. The seasonal distribution of discharge for river Prut is: 39% : 34% : 12% : 15%, respectively.

The barrages built on the large rivers (Dniester and Prut) changed completely their natural hydrological and thermal regime and adversely affected the river ecosystems. The regulation of all small internal water courses transformed most of them into a chain of ponds connected by streamlined canals collecting waste and surface runoff waters polluted with nutrients, oil products, detergents, heavy metals etc. The self-purification capacity of these river systems was heavily affected and only limited water life forms can survive in such habitats.

The current poor state of the surface waters in Moldova is a consequence of multiple and brutal interventions into the natural mechanism. The deforestation of watershed areas, intensive land use, draining the wetlands, river regulation, discharge of polluted wastewater, construction of many water reservoirs, all generated significant qualitative and quantitative changes in the hydrographical network of the Republic of Moldova.

The main water supply source for Moldova is the Dniester river (54% of total water use). River Prut contributes 16%, other surface waters, 7%, and the groundwater, 23%.

Groundwaters

The distribution of groundwater resources over the territory of Moldova is un-even, their major part is concentrated in the discharge areas along the Dniester and Prut rivers.

The Republic of Moldova has a large share of rural population (54%) and most villagers use groundwater for drinking and other purposes. There are 6,600 deep artesian wells across the country. In 2002, only 3,100 of them were estimated to be operational. The rest of them were abandoned and presently they do not belong to any legal owner. The shallow groundwater is used intensively in rural area being supplied through some 132,000 shallow wells and springs.

The deep groundwater reserves are, according to an estimate made in 1981 for a period of 25 years, 3,173,000 m3/day. In 2001, 874 million m3 of water were used, of which 138 million m3 - from groundwater. The reserves of shallow groundwater have not been estimated yet, but it is known that about 50,000 m3 of shallow groundwater are used per day.

By the purpose of use, the groundwater can be potable, mineral, industrial and thermal. All these types of groundwater occur on the entire territory of the Republic of Moldova.

The groundwater constitutes 32-35% of the total water used for centralized water supply in Moldova. Shallow aquifers are used for non-centralized water supply and the share of shallow groundwater in rural area reaches 95-100% from all water used.

From the total groundwater reserves (3,173,000 m3/day), 2,602,000 m3/day are potable water reserves and 573,000 m3/day are technical water reserves. The Republic of Moldova is reach in mineral waters, with aquifers situated at 200 - 1000 m depth. To date, 16 deposits of mineral waters have been prospected. Mineral waters are categorized as potable and curative waters. Potable mineral waters spread all over the country. The most commonly known are: Varnita, Balti, Chisinau, Soroca, Camenca, Hirjauca, etc. The water mineralization is between 1.0-10.0 g/dm3. Curative mineral waters mostly occur in the South and North-East of the country. They contain hydrogen sulphide (30,0-80,0 mg/dm3), iodine (17,0-26,0 mg/dm3), bromine (132,0-139,0 mg/dm3) and other chemical elements (lithium, radon, strontium, boron). An example of good use of curative mineral water is the “Nufarul Alb” complex in Cahul.

Industrial groundwater contains rare chemical elements, which can be extracted. Waters containing iodine (1-60 mg/dm3), bromine (20-250 mg/dm3), helium (up to 15.0 ml/dm3) and boron are prevailing.

Thermal waters occur in the Prut river floodplain and in the South of Moldova. The temperature of water is 20-800C and the yield, 10-100 m3/day.

The total water resources available for various purposes are estimated at 7.1 km3/year, including internal surface water resources (1.32 km3), the groundwater (1.1 km3), and the share of Moldova from transboundary rivers, Dniester (4.1 km3) and Prut (0.7 km3). This did not include the ecologic water shares of the Dniester river (2.5 km3) and the Prut river (0.8 km3). The per capita water reserves in Moldova (deriving from local sources) are about 330 m3 per year, or 1,700 m3 per annum, taking into account the share of transboundary rivers. Related to 1 km2 of national territory, this accounts for 211,000 m3, including water of the bordering rivers, and only 38,900 m3 from local sources [30, 40].