Showing posts with label road curbs. Show all posts
Showing posts with label road curbs. Show all posts

Monday, 9 January 2017

Landscape : Curbing the Curbs 3

If the main role of road curbs are to keep vehicles on the road, and preventing them off the green area and especially walkway, then it can be easily replaced with guardrails. 

In Malaysian environment, weather is a nuisance. There are times when it rains so heavily, causing flash floods ; and there are also times when there is not a single drop of rain for weeks. 

Cambered asphaltic concrete road (A) allows fast flow of water off the road surface.  If the surface water are directed straight to the drain (C), there will be minimal water seepage through the green area.

However, if the green areas are designed conclave to trap water (B), not too much of course, just enough for some water to seep into the ground and thus more water available for trees and shrubs. 


The water from watering tank during dry spell too will be more effectively seep into the soil, mineral soils especially. In addition, it also trap the fertilizer from being easily washed away.





Wednesday, 10 April 2013

Landscape : Curbing the Curbs 2




Road curbs, when wrongly placed, or poorly maintained, literally curb the rainwater from flowing away from the road, thus keeping the rainwater on the road surface.  When curbs defeated its purpose, road become streams of waterway.


Not only the scupper/discharge drains are not sufficient to direct the water to storm drain, they are clogged with sands and vegetation as well.   Over time, sand and earth form vehicles accumulate at the road edge. Yet, instead of sweeping the sand away, they were dumped on the road shoulders.






It does not need an civil engineer or a town planner to realize that the curb is not serving its purpose.

Obviously, there are other reasons.  I can imagine some :
1. incompetent architects designed the road.  They are either ill-equipped with the knowledge, or with ill-intention ;
2. deceitful contractors cut corners in doing their sloppy work ;
3. cheating maintenance contractors not doing their job ;
4. corrupt government officials closed one of their eyes ;
5. damaged of pipes by third-party contractor ;
6. and yes, we could blame the weather : it rains too much !


Or, we can just do away the curbs.   For new projects, level down the road shoulders so that rain water can flow freely to the storm drain.  That should settle the problem once and for all.

However, for the existing problematic curbs, either spend a perennial sum to maintain and repair the drains, or spend a lump sum to level down the shoulders.  Of course, the government can always find whoever created the mess, and make them pay.  



Just in case, for those who don't know how's the look of a road without curbs, check out the photo below.

Wednesday, 1 June 2011

Landscape : Curbing The Curbs

Road curb or kerb, is the edge where a raised footpath, road median or road shoulder meets an unraised roadway.  It is typically made from concrete, asphalt or long stones.



Ideally …

Curbs are designed to guide water from melted snow and rain into storm drains.  It also keeps vehicles on the road.  Curbs also add to the aesthetic aspect of the road.

Since curbs add to the cost of a road, they are generally limited to urban and suburban areas, except where certain drainage conditions make them necessary.  However, curbs are not universally used, even in urban settings.



In reality …

Poorly maintained curbs often results in ponding of water.  Sand and dirt from vehicles, blades of grass leaves, debris and rubbish accumulate at drain.  After some time, the sand and debris become growing bed for weeds.  Soon the curb will be infested with weeds of all sizes !

Often after heavy downpour, surface rainwater find limited outlet to drain out of the road.  The curbs acts as a retention wall to keep the water in, while the scupper drains hardly suffice to drain the water in time ( as diagram below ).   It is not hard to find Malaysian roads flooded during heavy downpours, no thank to curbs !

Big puddles can be dangerous, as they can cause hydroplaning at higher speeds and loss of control of a vehicle.  At times, water can spray from tires onto following vehicles, causing poor visibility.  Also the unfortunate are pedestrians and motorcyclists who were splashed by hydroplaning.

Prolonged ponding due to blocking of water by curbs eventually leads to deterioration of asphalt concrete roads.  Over time, the damaged asphalt widened and deepened.  Potholes posses danger to motorists, especially motorcyclists, the least, damage the vehicle's tires and suspension system.

At the end of the day, all the shortcomings and damages translate into monetary losses.  Additional cost to construct the curbs, extra earth to level up, sweeping of sands, rubbish collection, weeding etc… all at our expense, the ratepayers.  For sure, someone is making a profit out of it.



To consider …

There are no doubts that curbs do serve their purpose, providing there are rightly located.  There are places for them, there are places not for them as well.

While it may be feasible to have curbs at pedestrian-heavy urban and housing estates, it may not necessary for highways, trunk roads and any other road with low pedestrian users. 


Cambered asphaltic concreted road, tufted soil/walkway should be leveled to allow smooth flow of water into the storm drains ( as diagram above ).  It may seems inconvenience for pedestrian as the water from the road, flowing pass the walkway.  But who would walk down less-travelled road during heavy downpour ?