Commissione europea

Associazione Lago di Bolsena volontariato


September 2nd 2018

To:European Commission

Directorate-General Environment

e-mail :


Copy to:

PETI Secretariat


petition 2191/2013


Dear Sirs,

Thank you very much for your letter ENV.E.2 / MG / am / Ares (2018) [Ares(2018)1362298] of 12 March 2018.


As further supporting material regarding the state and evolution of the lake, I now enclose an international scientific publication: Long-term change in the trophic status and mixing regime of a deep volcanic lake (Lake Bolsena, Central Italy) by Rosario Mosello, Piero Bruni, Michela Rogora, Gabriele Tartari, Claudia Dresti , published in Limnologica 72 (2018) 1-9 (2018).) Specifically, illustration 8 (page 8) demonstrates the stable trend of increasing the concentration of phosphorus in the lake, and the fact that, in 2017, the total concentration of phosphorus TP has exceeded the threshold of 15 μg / l which means a "sufficient" trophic state.


This classification is shared by the ARPA Lazio, the official body responsible for assessing the lake’s ecological status which in its summary of the results for the three-year period 2015-2017 (attached) classifies the water quality of Bolsena lake as "sufficient". As mentioned earlier this classification is down from “good” which, according to the Italian authorities, prevailed in 2015 (cf. Commission reply to the petition Committee of 28 February 2015).


Your above mentioned letter of 12 March 2018 reflects inter alia the information transmitted by the Italian authorities to the European Commission. According to those authorities, work on the sewage system was started on 5 September 2017 and will be completed by March 2018. Actually, the construction site was consigned to the contractor on September 5th, but the works on the collector started in March 2018 only and are not yet finished. Work on the wastewater treatment plant, currently out of service, has not even started. Long before 5 September 2017 and ever since, a large part of the wastewater has ended up in the lake. The remaining part has polluted the river Marta up to its mouth in the sea in Tarquinia with an important load of nutrients and bacteria.


In a separate mail I send a film of 40 Mb that, by way of example, shows wastewater spills into the lake at three points in August 2018. The first two examples concern wastewater spills from the pumping stations 9 and 13. The third example shows the effect of a wastewater spill into an affluent ditch in Capodimonte.


Moreover, the scope of the works so far awarded is itself limited, to a point that raises serious questions about their actual effect. Thus, the tender did not include the revision of the status of the pipes between pumping stations, nor did it include revision of all the stations, some of which will therefore remain in the state in which they were before the works. The official tests of the system envisaged at the end of the works under way will therefore have a partial value only. They will be confined to the results of the works actually conducted and will not provide any indications on whether those pipes are leaking and hence whether the overall system will be properly functioning.


Besides, the question of the future management of the sewage system of the lake's reservoir and the financing of management and maintenance remains unresolved.


With reference to our document "State of the Bolsena lake, year 2017" please be informed that nothing is planned to complete the missing part of the collector (so far unjustly called “round the lake” collector), on the west side of the lake. Likewise, nothing is planned to repair and enhance the collection networks of the individual municipalities (and which are estimated to represent 20% of the phosphorus pollution of the lake; cf. State of the Bolsena Lake, year 2017, page 24). As regards agriculture, equally referred to in the above document as one important source of phosphorus pollution, financial incentives have been provided by the region in favour of hazelnut plantations (see PSR of the Lazio Region, accessible through this link:, even though these plantations are notoriously polluting. No additional incentives, specific to the hydrological basin of the lake, are provided in favour of agricultural activities compatible with the objective of protecting the lake.


However, without measures addressing all those other sources of pollution, it is unclear how a further deterioration of the lake could be prevented and even less how the lake could recover to its previous “good” status (cf. State of the Bolsena Lake, year 2017, page 24).


On the basis of the above and all the other evidence provided so far, I hereby formally complain about the violation, by Italy, of its obligations under the Water Framework Directive, No 2000/60/EC.


Nutrient reduction measures are part of the conservation measures established by the leading experts of the lake's ecosystem and approved by the Province of Viterbo in 2010. These measures are based on a large general study funded by the EU and meet the criteria established in the Habitats Directive. The Lazio Region has instead adopted conservation measures that do not meet these criteria. Consequently, I reserve the possibility to lodge a formal complaint regarding the violation of the Habitats Directive, No 92/43/EEC.


I have been invited to Antwerp on September 18th as a guest speaker in the opening session of the INSPIRE conference. It will be the opportunity to talk about the involvement of citizens in the protection of Lake Bolsena.


Very truly yours.


Piero Bruni


Representative mail address:

(official contact for correspondence)

Piero Bruni Via Pio Fedi 77

I-50142 Firenze



Association Address:

(submitting the complaint)

Associazione Lago di Bolsena

Via 25 Aprile

I-01010 Marta VT