Our waterways are becoming greener by the day, writes Will McCallum, Hackney resident and Greenpeace.

Large patches of bright duckweed get bigger overnight, merge together and slowly start floating towards the Thames, taking over locks and choking narrowboats. The hot summer days which have had us outside in the park and having barbecues with friends have led to the annual explosion of this little plant. It can be a little alarming, our waterways suddenly covered by a thick spongy mat.

Over just a few weeks the River Lea starts to resemble a swamp, with clumps of rubbish poking out to provide a mid-river perch for coots and moorhens. To the birds, duckweed can be like manna from heaven – a plant rich in protein. Some people even joke it could become the next gourmet must-have for north London’s foodies.

It can get problematic, though, and the Canal and River Trust often has to step in to try and clear the duckweed before it gets too thick.

It can grow so quickly, the patches soon become inches thick, which can harm the life that swims and crawls beneath the surface by denying it light and oxygen.

The rubbish can be disgusting as well, resting on the surface as a constant reminder of our dirty litter habit.

Despite all this, I like it – a reminder of how the world around us changes with the seasons. As I cycle each day along the canal from Victoria Park to Angel and back I watch the green leaves gradually carpeting the water, only to disappear again in a few weeks’ time as the days get shorter.

The Gazette entitled Kim Wright’s letter about the Britannia Leisure Centre “No truth in leisure centre rumours”, writesPat Turnbull, Handley Road, Hackney.

These aren’t rumours. Since 2013 Hackney Council has been planning to demolish the Britannia Leisure Centre and replace it with 176 dwellings for market sale – described by Kim Wright as “some housing”. The plans were published in the Hackney Site Allocation Local Plan in that year.

We don’t need “a new and improved leisure centre”; we have one, in the Britannia Centre, that includes a leisure pool with wave machine, a gym, a football pitch and meeting rooms, in an attractive low rise building with pleasant gardens.

It is not even old, having been built in the 1970s and 1980s. It provides facilities for all ages, and for families and single people.

Hackney Council should not be trying to set itself up as a developer, to fill our borough with yet more expensive housing. It should be meeting the leisure and housing needs of its current population. Demolishing leisure facilities and building expensive tower blocks of flats does neither.

The new proposal to put a school in the mix adds a new twist to the tale.

A school at the bottom of a block of flats does not meet the needs of the children who attend it. A school should be a free standing building with plenty of space round it for children to play in.

It was not that long ago that every school in Hackney fulfilled those criteria.

Hackney Council’s desperate attempt to use the inflated and precarious London housing market to finance services is in danger of saddling Hackney residents with problems they will have to deal with for decades to come.

That is why I ask for a full and widely publicised consultation, involving all Hackney residents, on these proposals.

Congratulations to Tyssen pupils, writes Paul Fennell, engagement manager, Intellligent Health.

I’d like to extend my personal congratulations to residents in Hackney and east London for the collective achievements in the “Beat the Street” game. Over the last six weeks, more than 29,000 residents have walked, run and cycled 54,325 miles throughout the area – the equivalent of 10 times the length of the Great Wall of China.

Through their participation, many will have taken their first steps towards improved health.

Tyssen Community Primary School travelled the furthest in Hackney, walking more than 2,500 miles. The winning teams will be collecting their prizes at a special celebration event in September.

Thanks to funding from the National Charity Partnership between Diabetes UK, British Heart Foundation (BHF) and Tesco we have been able to inspire the whole community to get moving.

Being more active can really help reduce a person’s risk of Type 2 diabetes and heart and circulatory disease.