Diversion of eel by means of light in the river Overijsselse Vecht, Netherlands

At three locations in the large rivers in the Netherlands hydropower plants are in use which damage the fish population, mainly eel. One of the options to decrease the damage is to divert the eel from the inlet systems and to guide them past the plant via a bypass. Near one of the plants, in the river Overijsselse Vecht, nets and fykes are placed. A light screen of 28 light bulbs (42 Volt, 200 Watt) is installed on the bottom of the river to deter the downstream migrating eel and to divert them to the fykes alongside the river bank. In a period of 126 consecutive nights the bulbs were switched on every other night. The eel catch of each night was determined. It appeared that 73% of the downstream migrating eel was diverted by the light screen