Case Study 1: Idro Lake and Chiese River Basin
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euwareness italy Case Study 1: Idro Lake and Chiese River Basin Bruno Dente and Alessandra Goria Case Study 1: Idro Lake and Chiese River Basin Bruno Dente Alessandra Goria April 2002 Istituto per la Ricerca Sociale (IRS) Via XX Settembre 24 20123 Milano Italy Tel: +39.02.467641 Fax: +39.02.46764227 Website: www.irs-online.it Email: [email protected]; [email protected] EUWARENESS is a research project on European Water Regimes and the Notion of a Sustainable Status. Research institutes from six European countries (Netherlands, Belgium, France, Spain, Italy, Switzerland) have been cooperating in this two year project (2000-2002). More information is available on www.euwareness.nl. The project is supported by the European Commission under the 5th Framework Programme, and co-ordinated by the University of Twente in the Netherlands. Contents 1. Geographical and hydrological characteristics of the water basin ............................................................ pag. 3 2. The chronology.............................................................................................................................................. pag. 6 3. The actors involved ..................................................................................................................................... pag. 14 4. The definition of the problem...................................................................................................................... pag. 21 5. The evolution of the Idro Lake institutional regime................................................................................... pag. 24 6. Analysis of the Idro Lake regime change .................................................................................................. pag. 28 7. Qualification of the regime change ............................................................................................................ pag. 29 8. Conclusions................................................................................................................................................. pag. 32 References ......................................................................................................................................................... pag. 33 Main actors interviewed ................................................................................................................................... pag. 34 Annex 1: Press review and chronology (in Italian)......................................................................................... pag. 35 Annex 2: Interviews’ report (in Italian) ........................................................................................................... pag. 74 1. Geographical and hydrological characteristics of the water basin The Chiese river generates from the Adamello glacier and flows down the Daone Valley, providing water to two artificial lakes: Malga Bissina, at 1791 m. a.s.l., and Boazzo, at 1225 m. a.s.l.; the river then flows through the Giudicaria Valley, and generates the Idro Lake at 369 m. a.s.l.; finally flowing down the Sabbia Valley it joins the River Oglio. The Chiese river flows across two regions: Trentino and Lombardia, and along 148 km of land, of which 49 km belong to the region of Trento, 83 km to the province of Brescia, and 16 km to the province of Mantova. The whole water- basin covers 934 km2, including 2,5 km2 of glacial area. The average altitude of the water-basin is 1230 m. a.s.l.; within the territory of the water basin there are high peaks such as Mt. Fumo (3.441 m), Mt. Crozon di Lares (3.354 m), Mt. Carè Alto. Rainfall in the area is quite high: historical data from the Hydrological Annals for the period 1934- 1942 and 1947-1984 show an average yearly rainfall of 1.461 mm. Based on the same data sources, the average yearly water flow in Gavardo (downstream) amounted to 33,8 m3/sec (36,3 m3/sec in the month of August): these values are obviously influenced by the lake regulation. The Idro Lake is a natural basin artificially regulated: the average surface of the lake amounts to 11 km2, with a carrying capacity of 75.500.000 m3 of water at an average altitude of 367,5 m. a.sl.. The shore of the lake develops along 24 km; its length in a bee-line is 9,75 km, and its maximum width is 1,90 km. The whole catchment basin covers 617 km2. The hydraulic works which allow to regulate the water out-flows from the Lake are: - the dam, with a maximum out-flow capacity of 220 m3/sec, above the threshold of 367 m a.s.l - the Enel Gallery, which provides hydroelectric power to the power plant in Vobarno, with a maximum out-flow capacity of 32 m3/sec, above the threshold of 360,5 m a.s.l. The gallery releases the water in the Chiese river at Vobarno - the Farmers’ Gallery, with a maximum out-flow capacity of 100 m3/sec, above the threshold of 360 m a.s.l Figure 1. A sixteenth century map of the Idro Lake Figure 2. A scheme of the Idro lake and Chiese River water basin Bissina 60.045.000mc Boazzo 11.769.600 mc Idro Lake ENEL Gallery 75.000.000mc Gallery of Farmers (lake-bed discharge) Vobarno ENEL Hydro-power station Dam Gavardo Big Irrigation Small power-plants Canal of self-producers [5] [55% of water] Bedizzole Irrigation Channels [45% of water] 2. The chronology The sources used to reconstruct the chronology of the decision making process in the Idro Lake case were essentially the articles from the national and local newspapers, as well as the formal and informal documents issued by the actors involved and relevant to the process, and the in-depth interviews conducted with the same actors. The most important events1 in the evolution of the Idro Lake regime in the last two decades can be identified with: 1987 ⇒ expiration of the concessions for irrigation from the river Chiese, entitled to 4 Consortia2 in the Province of Brescia. The concessions dated back to very old regulations: the R.D. 262-264/1937 and the D.M. 4696/1950, which allowed an overall withdrawal of 24 m3/sec. In 1987 the 4 Consortia present a formal request for the concessions’ renewal, with the special request to amend the additional flows which they have been withdrawing since the early 1960s, after the creation of the two artificial upstream basins of Bissina and Boazzo. These two basins made available around 12 millions of m3 of water, the so called ‘newest’ waters, allowing for a marginal increase in water flows of 4,2 m3/sec October 1987 ⇒ expiration of the concession to the Lake Idro Company (henceforth SLI) to construct and manage the works to regulate the Lake Idro waters. The concession dated back to the R.D. 8/1927. The SLI was created in 1922 to construct and manage the hydraulic works needed to transform the Idro Lake into an artificial basin. The 1927 regulation defined the maximum water storage in the Lake at 370 m a.s.l. (with respect to the one previously allowed at 368m a.s.l.), and the minimum storage at 364,5 m. a.s.l.. With the law 22/1932 the minimum water storage was set at 363 m. a.s.l., allowing for an overall variation of 7 m in the water levels. The regulation of the lake currently continues in prorogatio de facto based on two main regulations, aimed at fulfilling essentially hydroelectric and irrigation needs: - the ‘Newly added regulation for the basin’ dating back to 1927 - the ‘Regulation to co-ordinate the functioning of the hydraulic works in the Alto Chiese (up-stream) with those of Lake Idro’, dating back to 1958. ENEL (National Body for Electric Power), which after the nationalisation in 1963 took the place of SEB (Electric Company of Brescia), is entitled to the concessions to withdraw water for hydroelectric use from the upstream artificial basins: these concessions are not subject to expire. SLI was owned by SEB (50%) and Università del Naviglio Grande (50%). The ownership structure of SLI was modified when concessions were transferred from SEB to ENEL, which was forced (by law) to reduce its capital share to 5%. The Consortia currently hold the majority share. ENEL has one representative in the board of directors September 1988 ⇒ at the expiration of the concessions entitled to the Consorzio Alto Mantovano for irrigation from the river Chiese (regulated by R.D 2689/1921, D.I. 35/1958, D.I. 741/1974), the Consortium makes a request for concessions’ renewal. The Consortium does not require any additional water. Traditionally the farmers’ Consortia from Brescia and Alto Mantovano had been in conflict with regard to water off-takes; in 1953 however they found an agreement (so called ‘Peace of Chiese’), whereby the overall water flow for the big off-takes was supposed to amount to 27,7 m3/sec: additional 3,7 m3/sec of water (on top of the 24 m3/sec acknowledged to the Consortia from 1 In the Appendix (in Italian) all the articles from the local and national press from 1992 onwards are reported. 2 Università del Naviglio Grande Bresciano (the big irrigation canal), Roggia Maggiore Calcinata, Utenti Roggia Lonata, Naso Generale di Montichiari (smaller irrigation channels) Brescia) were acknowledged to the Consortium Alto Mantovano for the irrigation season January 1990 ⇒ the Consorzio di Bonifica del Medio Chiese starts to operate. The Consortium3 reunifies 16 Consortia in the area of Brescia, including Roggia Maggiore Calcinata, Utenti Roggia Lonata, Naso Generale di Montichiari, Università del Naviglio Grande Bresciano, from which it inherits the majority share of SLI September 1991 ⇒ the Consorzio di Bonifica del Medio Chiese advances a formal request to succeed to the reunified