A model to estimate timing of aquatic weed control in drainage canals; Part 1

In many parts of the Netherlands a dense network of watercourses is necessary to drain the land. A related aspect is thechanging transport capacity of the water courses due to thegrowth of aquatic plants in the growing season. In turn thisphenomenon requires aquatic weeds to be controlled by waterboards in order to maintain the water course's required capacity.The procedure outlined in this paper can be used to determinethe frequency of weed control based on hydrological andhydraulic conditions. The drainage from groundwater gives anexpected variation in discharge over the growing season. Thepermissible flow rate is governed by both the growth of weedsand the permissible water levels in the water course. Weedcontrol is necessary during the growing season when theexpected discharge is more than the permissible flow rate. Thisprocedure has been incorporated in the model MWW(Maintenance of Water courses by Water boards). An examplehow to use MWW is given.