Wildflower.ie HomeWildflowers.ie



Free Quote


Price List






Contact / Find





Site Index


Native Seeds




Simple Beauty








Summer Long


Quick Guide


Yearly Guide


How-when 2 cut




Gap creation






Features index


Growers Manual


Flowers n' Grass






Market leaders








Pure Joy










Specialist Hort'


Plant Price List


Species Data



  Mail Order

Start Here

from every bag 

Seed Cert

Wild Native
seed, plants 
seed mixtures, 
25 years+


Bulk Discount

Glás or Greening 

B2B - Bespoke
Site Visits
Trade Prices



Start Here


  Handing on
our Heritage

Supporting Technical Paper 3.

Consideration of biological and landscape diversity in the development of navigable waterways

by Mr. Gijs Kurstjens, Wissel Consultancy, The Netherlands


In this study the effects of navigable waterways on landscape and biodiversity are presented. Two types of navigable waterways are distinguished: canals and regulated rivers.


Negative and positive effects of both types of waterways

The construction of canals (mainly in the past) has caused great loss of natural biotopes and a big barrier problem in the area being traversed. The problems are very similar to the ones caused by motorways and high speed trains. Besides this canals can have severe hydrologic effects (drying up of natural floodplains and marshlands) and negative effects on native species (by connecting separated catchments and giving opportunities for exotic species to invade new areas). 


Normally canals have little variation in biotopes but in some sections new, sometimes exceptional nature values have developed. In regulated rivers a large variation of biotopes and populations can occur depending on the degree of regulation. The measures for normalization and canalisation can cause severe negative effects on the natural morphology and hydrology of river ecosystems as well as on natural biotopes for the typical flora and fauna of floodplains. The worst effects are caused by dams changing rivers into nearly standstill canals and a chain of oblong lakes hardly passable for aquatic organisms.


Measures to solve the negative effects

Regulated rivers can be restored with the natural river in mind. Morphologic and hydrologic processes play an important role in natural rivers as well as biotic processes. For instance flooding and the occurrence of alluvial forest are typical for rivers. In dammed rivers streaming side channels can be constructed around dams as fish passage and biotope for rheophile species. In normalized rivers without dams old side channels can become alive by stimulating morphological processes or active digging out by man. In many places stony bank protection can be replaced by natural spontaneously grown alluvial forest with exception of locations where navigable problems can occur (in river bends) and bottle-necks in the river bed where problems can occur during floods.


Proposals of measures to ensure protection of biological and landscape diversity in future

In the case of canals possibilities to compensate for negative barrier effects of canals which fragment core areas of the Pan-European Ecological Network should be investigated. On the other hand management authorities for waterways should introduce ‘natural management’ along canals to gain a lot of ecological benefit and landscape improvement. In case authorities are planning to build a new canal it should be compulsory to carry out an impact assessment study as is the case with new motorways and railways. This legislation does not exist sufficiently in many countries outside the E.U..


Impact assessment studies for large-scale regulation works (dams and locks) in rivers should be made obliged by national law in all member states of the Council of Europe. Attention should be paid to conflicting laws existing in some countries. The legislation should be adjusted in order that both the barrier effect and the loss of (flowing) aquatic habitats due to dam construction should be compensated. 


Governments should put more efforts on the large-scale restoration of regulated river systems and emphasize measures based on the natural reference of particular rivers. For instance it is preferred to construct natural side channels in stead of fish passages to compensate for the barrier effect caused by dams. Financial means for restoration and nature development can be generated to combine measures for navigation with measures for safety, extraction of drinking water and tourism.

  Legal | Product Warning.| Refund and CancellationPayment Terms

Sandro's Famous Seeds. Start Here

Handing On Our Heritage -  Hand picked quality perennials

EU Plant Health Pass: EUPP/IRL/DAFF/2684.

Great Irish Horticulture

Mr. Sandro Cafolla t/a  Design By Nature  (Ire). Monavea, Carlow, Ireland. Eircode R93 T289 
Vat No : IE 3656298P | Business Registration: 109182 

Go on.. Choose - Design By Nature - Irish Native sourced Wildflowers