| River Thames at Thames Ditton Island including Boyle Farm Island | River Thames | Warning |
| River Thames at Thames Ditton Island including Boyle Farm Island | River Thames | Alert |
| River Thames from Shepperton to West and East Molesey including Hamm Court, Walton-on-Thames and Sunbury | River Thames | Alert |
| River Ivel from Langford to Blunham, including the rivers Purwell, Hiz, Flit and Hit | River Ivel | Alert |
| Trinity Marsh Ditch at Waltham Cross | Trinity Marsh Ditch, Small River Lee | Warning |
| The Radlett Brook at Radlett | Radlett Brook | Warning |
| The Upper River Colne and Radlett Brook at Colney Heath, London Colney, Borehamwood and Radlett | River Colne | Alert |
| The River Crane at Hillingdon, Southall, Cranford, Feltham and Twickenham | River Crane | Alert |
| River Lee at Luton, Harpenden including Wheathampstead and East Hyde | River Lee | Alert |
| Beverley Brook at Barnes, London Boroughs of Richmond upon Thames and Wandsworth | Beverley Brook | Warning |
| Beverley Brook area, including the Pyl Brook, in the London Boroughs of Merton, Sutton, Kingston upon Thames, Richmond upon Thames and Wandsworth | Beverley Brook, Pyl Brook, East Pyl Brook | Alert |
| River Thames from the River Brent to the River Crane including East Isleworth and Syon Park | River Thames | Warning |
| River Thames including areas in the boroughs of Kensington & Chelsea, Hammersmith & Fulham, Ealing and Hounslow | River Thames | Alert |
| River Thames including areas in the boroughs of Wandsworth and Richmond-upon-Thames | River Thames | Alert |
| River Thames from Raven's Ait to Teddington Weir including, Raven's Ait, the Hogsmill River below the university Knights Park Campus, both Kingston Bridge's and Steven's Eyot | River Thames | Warning |
| River Thames from Hampton and Thames Ditton to Teddington including Hampton Wick and Kingston-upon-Thames | River Thames | Alert |
| River Hogsmill area from Ewell to Kingston upon Thames, including the Surbiton Stream in Surbiton and the Green Lane Stream between Ewell and Epsom | Hogsmill | Alert |
| River Thames at Thames Ditton including Ditton Field and Ditton Reach | River Thames | Warning |
| River Thames at Teddington including Broom Road and Lower Teddington Road | River Thames | Warning |
| River Thames from Mortlake High Street East to Richmond Bridge including Mortlake, North Sheen, Kew, the Royal Botanic Gardens and Old Deer Park | River Thames | Warning |
| The River Ash in Hertfordshire including Furneux Pelham, Little Hadham, Much Hadham and Wareside | Ash | Alert |
| River Thames at East and West Molesey including Hurst Park, Buckingham Avenue and the Royal Mews area | River Thames | Warning |
| The River Ver at Markyate, Redbourn and St. Albans | River Ver | Alert |
| River Thames from Putney Bridge to Mortlake High Street East including Barnes | River Thames | Warning |
| The River Bulbourne at Boxmoor, Hemel Hempstead | River Bulbourne | Warning |
| The River Gade and Bulbourne at Boxmoor, Hemel Hempstead, Frogmore End, Kings Langley and Croxley | River Gade;
River Bulbourne | Alert |
| The River Colne at Colney Heath including North Mymms | River Colne | Warning |
| Beverley Brook at Worcester Park, including Motspur Park, London Boroughs of Kingston upon Thames and Sutton | Beverley Brook | Warning |
| River Thames at Kingston-upon-Thames town including, central Kingston, the area around Canbury Gardens and Albany Park Road | River Thames | Warning |
| River Thames at Trowlock Island including the Royal Canoe Club | River Thames | Alert |
| The River Colne at London Colney including Colney Street and Broad Colney | River Colne | Warning |
| The River Gade at Hemel Hempstead | River Gade | Warning |
| The River Gade at Kings Langley and Croxley, including Abbots Langley | River Gade | Warning |
| The River Mimram from Tewin to Hertford including Hertingfordbury | Mimram | Warning |
| The River Mimram at Whitwell, Welwyn, Tewin, Hertingfordbury and Hertford | Mimram | Alert |
| The Rivers Rib and Quin at Chipping, Buntingford, Braughing, Standon, Barwick, Wadesmill and Hertford | River Rib, River Quin | Alert |
| Beverley Brook at West Barnes, London Boroughs of Kingston upon Thames and Merton | Beverley Brook | Warning |
| The Radlett and Borehamwood Brooks at Borehamwood | Radlett Brook | Warning |
| The River Ash at Little Hadham, Hadham Ford, Much Hadham, Widford and Wareside | Ash | Warning |
| Beverley Brook at Raynes Park Including Beverley Way and Malden Golf Course, London Boroughs of Kingston upon Thames and Merton | Beverley Brook | Warning |
| River Thames from the Hogarth Lane Roundabout to the River Brent including South Chiswick, Grove Park, Strand-on-the-Green and Brentford | River Thames | Warning |
| The River Rib at Wadesmill to Hertford | Rib | Warning |
| The River Beane at Walkern including Holbrook | Beane | Warning |
| The River Beane catchment including the Stevenage Brook and the Dane End Tributary | River Beane, Dane End Tributary, Stevenage Brook | Alert |
| River Thames from Platts Eyot to Hampton Court Bridge, including Platts Eyot, area around Hampton Sailing Club, Garrick's Eyot, Taggs Island, Ash Island and Molesey Lock | River Thames | Warning |
| The River Ash at Furneux Pelham including Clapgate | Ash | Warning |
| The Mimmshall Brook at Warrengate Road including Water End | Mimmshall Brook | Warning |
| The Mimmshall Brook at Warrengate Road including South Mimms, Potters Bar, Brookmans Park and Welham Green | Mimmshall Brook | Alert |
| The Middle River Colne at Watford and Rickmansworth including Carpenders Park | River Colne | Alert |
| River Thames at Walton-on-Thames including Desborough Island, Walton Bridge and Elmbridge Leisure Centre | River Thames | Warning |
| The Stevenage Brook at Stevenage including Hooks Cross | Stevenage Brook | Warning |
| River Lee at Harpenden and Wheathampstead including East Hyde | River Lee | Warning |
| The River Beane at Hertford | Beane | Warning |
| River Hogsmill at Ewell Court, Ruxley and Old Malden, London Borough of Kingston upon Thames and Epsom and Ewell | Hogsmill | Warning |
| The River Quin at Braughing | Quin | Warning |
| River Rhee from Guilden Morden to Haslingfield | River Rhee | Alert |
| The River Rib at Buntingford to Barwick including Standon | Rib | Warning |
| The Dane End tributary at Dane End including Sacombe | Beane | Warning |
| The River Ver at St Albans including Sopwell, Park Street and Frogmore | River Ver | Warning |
| The River Colne at Watford including Bushey | River Colne | Warning |
| The River Crane at Cranford and Feltham including North Feltham | River Crane | Warning |
| River Thames at Hampton and Hampton Wick including Hampton Court, properties on the Barge Walk, Hampton Court Palace Golf Club and Hampton Court Road | River Thames | Warning |
| The River Mimram at Welwyn including Welwyn Garden City and Digswell | Mimram | Warning |
| The River Gade at Frogmore End including Apsley and Bennets End, Hemel Hempstead | River Gade | Warning |
| River Thames riverside from Putney Bridge to Teddington Weir | River Thames | Alert |
| The Rags Brook at Flamstead End to Cheshunt | Rags Brook | Warning |
| Beverley Brook at Wimbledon Common and Richmond Park including Kingston Vale and Robin Hood Gate and Roehampton, London Boroughs of Kingston upon Thames and Merton | Beverley Brook | Warning |
| The Tidal River Crane at Twickenham | River Crane | Alert |
| River Lee from Lemsford to Hertford including Welwyn Garden City, Hatfield and Mill Green | River Lee | Warning |
| River Hogsmill at Kingston, London Borough of Kingston upon Thames | Hogsmill | Warning |
| River Thames at Trowlock Island including the Royal Canoe Club | River Thames | Warning |
| The River Ver at Markyate including Flamstead, Harpenden | River Ver | Warning |
| The Small River Lee at Cheshunt including, Turnford, Holdbrook and Enfield Lock | Small River Lee, River Lee | Warning |
| The River Crane at Twickenham including Cole Park | River Crane | Warning |
| The River Mimram at Whitwell including Codicote | Mimram | Warning |
| Areas at risk of groundwater flooding in Kimpton and Lilley Bottom, including Lye Hill, Whiteway and Claggy Bottom | Groundwater | Alert |
| Areas at risk of groundwater flooding around Flamstead, including Trowley Bottom and Lower Sawpit Wood | Groundwater | Alert |
| The Tidal River Crane at Isleworth | River Crane | Warning |
| The River Ver at Redbourn including Redbournbury | River Ver | Warning |
| River Thames in the Sunbury town area, including Longwood Business Park, Halliford Road areas of Upper Halliford and Sunbury, Lower Hampton Road park, Kenton Court Meadow and Kempton Park Racecourse areas | River Thames | Warning |
| The River Beane at Watton-at-Stone to Waterford including Stapleford | Beane | Warning |
| The River Chess at Loudwater, Rickmansworth | River Chess | Warning |
| The River Colne at Rickmansworth including Batchworth, Money Hill and Maple Cross | River Colne | Warning |
| River Thames from Richmond Bridge to Teddington Weir including West Petersham and Ham Lands | River Thames | Warning |
| River Thames from the River Crane to Teddington Weir including St. Margaret's, Eel Pie Island, Strawberry Hill and East Teddington | River Thames | Warning |
| River Thames from Putney Bridge to the Hogarth Lane Roundabout including Fulham Palace, Craven Cottage, the Hammersmith Flyover, Furnival Gardens and South Chiswick | River Thames | Warning |
| Surbiton Stream at Berrylands, Alexandra, Surbiton Hill, Tolworth and Hook Rise, London Borough of Kingston upon Thames | Surbiton | Warning |
| Woolgrove Road, Green Lane, Purwell Lane, Brook View, Ninesprings Way and Oakfield Avenue in Hitchin, Stevenage Road in Ashbrook, Stevenage Road, Priory Lane and Elms Close in Little Wymondley, High Street and Church Lane in Graveley | River Ivel | Warning |