http://www.legislation.gov.uk/id/uksi/1999/672

SCHEDULE 3The Sea Adjacent to Wales

Article 6

The Severn Estuary

Point No.	Latitude				Longitude
1	51	34	09	N	02	42	33	W
2	51	33	51	N	02	42	27	W
3	51	32	30	N	02	42	52	W
4	51	31	33	N	02	47	04	W
5	51	27	19	N	02	59	28	W
6	51	25	30	N	03	01	33	W
7	51	21	29	N	03	06	13	W
8	51	21	24	N	03	06	51	W
9	51	20	58	N	03	11	02	W
10	51	17	43	N	03	14	31	W
11	51	17	09	N	03	18	18	W
12	51	19	17	N	03	38	46	W
13	51	23	49	N	03	57	30	W
14	51	21	38	N	04	26	30	W
15	51	24	16	N	04	37	03	W

The Dee Estuary

Point No.	Latitude				Longitude
1	53	20	17	N	03	12	56	W
2	53	20	20	N	03	13	23	W
3	53	21	04	N	03	14	41	W
4	53	24	13	N	03	17	44	W
5	53	25	30	N	03	21	17	W
6	53	27	07	N	03	24	30	W
7	53	31	34	N	03	31	52	W
8	53	33	18	N	03	34	09	W
All positions Ordnance Survey of Great Britain 1936 datum.