Blocked drains in London. Drain repairs and CCTV drain surveys carried out by J Snow Drainage London. J Snow Drainage London offer the very best service for blocked drains and CCTV drain surveys in London. Our London drainage company offers emergency drain repairs 24 hours day with a 1-2 hour response time, 365 days of the year. We're here for unblocking & clearing blocked drains, drain repairs, drainage maintenance, drain lining, drain replacements, drain jetting, gutter cleaning, emergency plumbing and CCTV drain surveys. We also offer an emergency plumber service in East London & most areas of North London too.