Walthamstow Reservoirs
From Londonbirders
Location
This group of various sized bodies of water lies north of Stamford Hill, East of Tottenham, south-west of Walthamstow and is bisected by Ferry Lane. The site is also sandwiched between Walthamstow Marshes [to the south-east], and Tottenham Marshes [to the north-west]. There are three reservoirs north of Ferry Lane: Lockwood, High Maynard and Low Maynard; and seven on the south side - Numbers 1-5 plus East and West Warwick.
Access
The main entrance is on Ferry Lane N17 where there is a car park. Permits both for fishing and birding purposes can be obtained at the gatehouse for £1 per day, or £8 for an annual permit (this also entitles you to a key for the East Warwick hide and to King George V Reservoir a few miles to the North). Whilst at the gatehouse, it is worth perusing the log book to see if anything interesting has been seen recently. The nearest tube station is Blackhorse Road, a 5 minute walk away. The complex is managed by Thames Water, and very popular with anglers.
Description
The larger reservoirs are typical in having concrete banks and, at first glance, offer little to tempt any passing migratory wader. The other lakes have the appearance of those you are left with after gravel extraction has taken place.
Although a visit at any time of year can be rewarding, the site can be quiet in the summer except for the large numbers of breeding Cormorants, Grey Herons, Tufted Ducks, Lesser Black-backed Gulls and Common Terns. The reservoirs hold nationally important numbers of Tufted Duck in the early autumn during July to early September their numbers will peak at about 2000!
In winter, relatively large numbers of ducks and geese can be present, and it is always worth checking the adjascent filter beds on Coppermill Lane for gulls. The best time of Mediterranean Gull is March (though one has overwintered recently) and November for Yellow-legged Gulls. There are a number of islands, each of which has its own character. The island on East Warwick usually holds breeding Lesser Black-backed Gulls, Herring Gulls and a few Common Terns in summer (also found on the few breeding rafts scattered around the site), and is a favoured spot for Lapwing. Reservoirs No.2 & No.3 hold the heronry, nesting beginning in early February. On the No.5 islands is the famous Cormorant colony - the population numbers around 300 pairs, with most activity from late February to late July.
If you wish to see passage waders however, it is worth visiting the site at first light, as they do have a habit of disappearing after flushing. If a reservoir is drained anything could occur. Note that during persistent rain, waders appear throughout the day. If you fancy your chances of finding a scarce Diver or Grebe, keep your eyes open; the last Black-throated Diver crashed into pylons and landed in the Coppermill Stream, beside the Low Maynard.
With this group of reservoirs lying next to the river Lea [being part of the Lea Valley Regional Park], it is likely that birds use the river for navigation, and therefore anything can turn up. There did used to be quite a sizable flock of Tree Sparrows frequenting the centre of the site [near the island with breeding herons], but they died out during the mid 1990s. Other small birds to keep an eye out for are Wheatears, Whinchats and Stonechats, but it is also worth grilling any pipits and larks for waifs and strays.