By Aleem Maqbool
BBC News, Gaza Strip
Sewage workers say the plant badly needs spare parts
For over a year, Israel has allowed little more than basic humanitarian aid into Gaza, as a means of isolating Hamas and stopping militants firing rockets into Israel.
A ceasefire between Israel and Hamas two months ago was meant to lead to the easing of restrictions, but progress has been slow, and frustration is rising.
In the dank basement of one of Gaza's sewage pumping stations, raw sewage sprays out of leaks in the rusting metal work.
The Strip's sewage system is one of many things affecting Gazans' quality of life that urgently needs updating.
"It took months and months of negotiations to get Israel to allow some spare parts through the borders," says Maher al-Najjar, an engineer at the Gaza Emergency Water Project.
"What we really need is for things to be modernised. We have funding and planning, but Israel won't allow the machinery in."
As it is, most of Gaza's sewage cannot be treated properly, so tons of raw waste flow straight into the sea.
"It's affecting our port, it's affecting the fishermen, it's affecting the fish we eat and the people swimming in the sea," says Mr Najjar.
"The sewage has no border and has spread right along our coastline."
Less than 20 metres away from a sewage outlet, we find Abdullah, 27, standing up to his chest in the water and casting his net.
He has been fishing for a living since he was 12.
"What can I do, I have to make money from the sea," he says. "You've seen Gaza, there are no jobs, I can't worry about my health."
Since the ceasefire began, the fighting with Israel has died down, but the strict sanctions remain.
Most of the one-and-a-half million people living in Gaza are now reliant on food aid, and are unable to enter or leave the strip.
Over the last year, tens of thousands of people in Gaza have lost their jobs.
Most industrial operations have stopped because raw materials are not being allowed into the territory, or produced goods allowed out for export.
The Pepsi soft drinks plant is one of only a fraction of Gaza's factories that are still operating.
One of the managers, Ahmed Yazji, 61, says his vast store room used to be filled with ingredients. Now it is almost empty.
"Since sanctions, it is very difficult to get the ingredients I need," he says.
"We have had to cut production drastically to keep going.
"I thought things would improve with the ceasefire, and that more things would be allowed into Gaza, but nothing changed, nothing changed at all."
Industry is undoubtedly still suffering badly, and local economists say it will take years to recover, even if freedom of movement of goods and people were to be granted immediately.
However, some things have improved since the truce.
After months of severe shortages, more fuel is being allowed into Gaza, for vehicles and for the electricity plant.
A limited number of other products, like clothes and shoes, are also getting in.
Factories have been hit by export and import restrictions
On the whole, though, the UN says the low volume of such goods arriving means they have not significantly improved living conditions.
The Israeli government says it has every intention of carrying out its commitments under the ceasefire agreement, and easing restrictions on Gaza.
However, it says it first wants to be sure that Hamas is also ready to abide by its obligations and stop militants firing rockets at southern Israeli towns.
Hamas has managed to reduce the number of attacks dramatically, but some rockets are still being fired.
Israel has also curtailed airstrikes and other military operations - although recent inter-factional fighting among Palestinians means Gaza has not rid itself of violence.
A matter of weeks ago, Shifa Hospital in Gaza City was receiving dead and injured almost every day from the latest Israeli operations.
That, for the time being, is no longer the case.
But people here are worried that unless the relative calm is backed up by a much fuller lifting of sanctions soon, frustrations in Gaza will rise, and could be the reason the fragile truce collapses and violence erupts again.