There are also reservoirs on the Vistula itself, such as Goczałkowice on the Mała Wisła (Small Vistula) and Włocławek on the lower Vistula. The disastrous 1934 flood prompted intensive work on the flood control system on the Vistula’s mountain tributaries. To reduce flood risk, flood protection reservoirs at Porąbka on the Soła (completed in 1936) and at Rożnów on the Dunajec (1941) were
constructed; half a century later, another reservoir was built at Czorsztyn on the Dunajec. The flood protection system in the Odra river basin consists of embankments, weirs, reservoirs (including dry flood protection reservoirs, i.e. polders), and relief channels. In the nineteenth century, the length of the River Odra from Racibórz to Schwedt was made 26.4% APO866 purchase shorter by digging channels. Regulation has continued since then. There are 23 weirs
on the Odra itself (19 built before the end of World War Two), serving principally navigation and hydropower. There are also several reservoirs on the Czech tributaries of the Odra. However, the total capacity of water storage reservoirs in Poland is only 6% of the mean annual runoff. Several reservoirs are sited in the southern, highland, part of Poland, but in the lowlands, and Poland is a predominantly see more flatland country, construction of a dam necessitates the inundation of a larger area. There is a recognised need to strengthen flood protection systems for larger towns like Sandomierz on the Vistula and Opole and Wrocław on the Odra. Past floods such as those in 1997 and 2010 have exposed the inadequacy of existing structural defences. Structural measures physically modify the environment, whereas nonstructural measures change people’s behaviour. Indeed, we must change our behaviour (software), and not just build defences (hardware).
The Polish people are increasingly acknowledging the importance of non-structural flood protection. One of the options being considered Branched chain aminotransferase is watershed management (‘to keep the water where it falls’ and to reduce surface runoff and erosion) and the restoration of wetlands and flood-plain forests, re-connection of old river arms, and identification of areas-to-be-inundated in an emergency. There is a call to ‘give more space to the rivers’. Further, legal regulations are being implemented/envisaged related to the use of flood-plain areas, such as restrictions on new infrastructure and on handling substances dangerous to water in households. It is important to improve social awareness of the flood risk. Early warning (Kundzewicz 2012) is an important part of any flood preparedness system, reducing the destructive impact of floods on vulnerable areas in terms of lives and material damage.