Cardiff Bay (Wales) 27 Oct., 2018
Keyword: Estuary, Port redevelopment, Water gate
I visited Cardiff to observe Cardiff Bay faces to Bristol Channel. I was expecting to observe a natural macro-tidal estuary with beautiful sedimentary structures and bedforms. But I could see artificial huge dam lake there.
Cardiff is capital of Wales and located in front of Cardiff Bay which faces to Bristol Channel and has developed as a port to export coals after Industrial Revolution (Fig. 1).
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| Fig. 1. Locality of Cardiff Bay. |
I visited the city but there were few things to see from a view point of sedimentology. So I moved to Penarth, south of Cardiff Bay, to observe beach faces to Bristol Channel with about 8 m in tidal range. Mainly gravel are distributed in the beach (Fig. 2) and mud and sand were partially distributed (Fig. 3). Ripple was developed only on sand and muddy areas were slightly higher than other areas (Fig. 4). It is very interesting how these sediment with various grain size transported and distributed like this.
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| Fig. 2. Beach of Bristol Channel in Penarth, south of Cardiff. |
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| Fig. 3. Gravel and mud were distributed. |
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| Fig. 4. Ripple was developed only on sandy areas and muddy areas were higher. |
Sedimentary rock was outcropped at the cliff in back of the beach (Fig. 5).
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| Fig. 5. Sedimentary rock in Penarth, south of Cardiff. |
The cliff is very dangerous because I saw the rocks with human-head size fallen from the cliff many times during my only two hours visit and probably supplies many gravels to the beach. The sediment seems to have wave ripple and shell beds but I couldn't observe the sediment in detail because of fallen rocks.
After the observation of the beach, I walked to Cardiff Bay along the beach and was surprised. There were huge levee (Fig. 6) and I saw beautiful clear blue water inside the gate(Fig. 7). Cardiff Bay is completely separated from Bristol Channel by huge levee (Fig. 8).
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| Fig. 6. Levee in Cardiff bay. Three people on the levee. |
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| Fig. 7. Inside (lower left) and outside (lower right) views of the levee in Cardiff Bay |
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| Fig. 8. Satellite image of Cardiff Bay. |
There are marina and people enjoy marine sports inside the levee. People also enjoy running and cycling on the levee, shopping and dinner in shopping mall and pub around the "bay". The "bay" was redeveloped to a stylish water front resort from a port for coal export after 1980's.
To observe tidal flat is as enjoyable as marine sports and shopping, I think (maybe many people don't agree with) .
