How to make a polder

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					             How to make a polder


                                    1. Low lying land is
                                    selected for reclamation




  SEA

             LOW LYING LAND



                                    2. A Dam is built. This
DAM                                 will eventually protect
                                    the polder from the sea.

                                    The Barrier Dam in
                                    Holland is 90m wide on
                                    top and carries a
                                    motorway.



                                    3. The sea water is
                                    pumped out of the area
                                    being reclaimed using
                                    pumps.

        Water pumped out            The dam has PUMP
                                    HOUSES which
                                    regularly remove water
                                    from the polder.
                                                        4. Salt loving plants
                                                        like MARRAM GRASS
                  Salt Loving Plants                    are planted. These help
                                                        absorb salt from the
                                                        soil.
                                                        It takes 5 YEARS
                                                        before a polder is ready
                                                        for use.




                  CANAL




5. When the polder is ready for use the land is ploughed and leveled.
Land uses are then allocated. These include farming, housing and
forestry.
Canals are built to help drain water from the land.