| Changes to the hydrogeological processes in dryland catchments, triggered by land clearing, often take many decades to reach a new equilibrium. |
| Engineers looking at flood defences, modelling catchments, sewer systems and watercourses take many factors into consideration. |
| The catchments of these basins may have a very large surface area, collecting run-off from a vast region. |
| Tectonic uplands bordering active faults are usually drained by steep catchments feeding alluvial fans, adjacent examples of which coalesce to define continuous bajadas. |
| If the latter was the case, there could be a higher risk of winter flooding in a number of the region's river catchments. |
| He also recommends that all specialist services should be concentrated in major hospitals that serve big population catchments of between 350,000 and 500,000 people. |
