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 The Samaan Grove Wetland System

Creating the Wetlands
by Kevin Kenny - Click images to enlarge


Construction of the Lakes
One of the main challenges in constructing ponds on the estate is the hard coral surface that exists in many places. When EDSA, the landscape architects, laid out the lakes they did not know the exact boundaries or structure of the coral formations. As the project progressed we found that coral formations would dictate the placement, dimensions, depth and size of many of the ponds. It became far too expensive to consider using mechanical equipment to place them in the exact spot where the landscape architect wanted them to go.   


Pond carved from hard coral
A good example is the pond shown above which was dug out of an area containing hard coral. Had we known the soil condition before we sold the land we would not have placed this pond in this location. However, because of the commitment made to the customer we ended up digging the pond in the coral base as agreed. We also experienced problems with water levels in L1 and SWW#6 because the excavated coral sections were not properly lined with clay and leaked.  

The Wells

Another challenge we faced in the early design of the project was how to deal with periods of severe drought, which would result in reduced water flow through the wetland system. During the dry season wild fires burn many areas of the estate. Since the main purpose of the developed wetland was to improve the quality of surface runoff flowing all year round we had to find a way to keep the wetland productive.

We decided to develop a series of wells located at strategic points which would be used to supply water to the drains feeding the wetlands. It was a bonus that we subsequently found a spring at Samaan II.


This photograph illustrates the problem at SWW#6. The waterlilies were high and dry in May 2005 after the first dry season. Most of them and most of the bog plants survived this condition and were flourishing in July when the water level returned to normal.  


Canaan Village drain

Canaan Drain (D2)

A main drain that flowed through the estate came off of the Cannan Feeder Road south of the development. This drain carried the bulk of the liquid waste from Canaan village. We built a silt trap and trash barrier which are checked and cleaned frequently. We fenced the silt trap to protect children from the village, who were seen playing and catching fish in the trap area. This water flows through another new concrete drain at the back of the southern boundary wall of Samaan II, down through a series of steps and into Lake 2A. 



Silt trap and drain


Silt trap T2 


Step drain


Trash barrier

As the water enters Lake 2A it flows
through some coral rubble placed to
prevent erosion.


Lake 2A
These two photographs were taken one year apart.
The beautiful Samaan tree at the right is one of the
largest found growing on this part of the estate and
every effort was made to preserve it.

Next the water flows through a culvert under the second bridge (B2). As with B1 we installed a self-leveling pipe. From there water flows into Lake 2B, then down a spillway into an earthen drain. There was no coral encountered in constructing these two lakes and all the sides and bottom were sealed with clay found on the site.

Lake 2B when first constructed >



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