Nera (Danube) basin and it is not navigable. After the filling of the artificial Lake Đerdap, as a result of the Iron Gate I Hydroelectric Power Station which was finished in 1972, the mouth of the river into the Danube was flooded. In order to allow the optimal electricity production, the water level of the Nera at the mouth should not go below , while it must not exceed it if the flooding of the banks is to be avoided. Since the mid-1990s, there are significant problems in fixing the river's level, as the process is costly and complicated. In 2018, representatives
Bracciola nera can be very productive and high yielding if not kept in check by winter pruning and green harvesting. In 2000, there 110 hectares (270 acres) of Bracciola nera planted in Italy, nearly all of it in the province of Massa-Carrara in Tuscany and the province of La Spezia in Liguria where it is a permitted blending varietal in the DOC wine of Colli di Luna. Bracciola nera destined for DOC wine production is limited to a harvest yield of no more than 12 tonnes/hectare. The wine is predominantly Sangiovese (60-70%) with Pollera nera, Canaiolo and Ciliegiolo collectively needing to make