Suddenly it seems we have enough water- or do we?

In  2022, when Water Neutrality restrictions were in place across the SNWRZ (which includes the entire Horsham District), Southern Water participated in an independent  water consultants’ review  covering water supply and future demand in the district  commissioned by Crawley Borough Council, Horsham District Council and Chichester District Council.  That review concluded (see chart below) that even if houses constructed in accordance with Water Neutrality requirements met the daily (but in reality totally unachievable) consumption target of 85 L per person per day, there would still be an annually increasing shortfall  in water supply versus demand to the end of the survey period (2040).

In 2025 Water Neutrality requirements were lifted following Government intervention. This intervention was not triggered by any evidence or credible belief that Southern Water had/would have access to adequate water supply to meet both existing and future development demand across the SNWRZ . Rather, it was triggered by the Governments frustration that the application of Water Neutrality requirements was very inconveniently undermining the achievement of its cornerstone election pledge of “kick-starting” the UK economy by delivering 1.5 million new homes during its first term. A target which the Labour Party leadership consulted the housebuilding industry on before their election, and was told was simply not achievable (a message which the industry has repeated to the government many times since the election). Nevertheless the Government persisted before and since the election with this fictional target and in its vain attempt to achieve this has ripped up longstanding planning protections for productive agricultural/rural land, land which is essential to trying to reduce the UK’s alarmingly increasing dependence on imported foodstuffs. And with its manipulation in scrapping Water Neutrality, without any credible evidence to support this decision, it has shown a complete disregard for the availability of water supply for the residents, current and future, of the SNWRZ/Horsham District.

Following the withdrawal of Water Neutrality, new build proposals across the district will as a result of the decision taken by HDC Planning, only need to demonstrate theoretical (not actual) water efficiency based on 110l/p/d, further increasing the supply/demand shortfall. In reality, the average daily water consumption in the district, based on the recently circulated figures from Southern Water is between  125 and 150L per person per day (based on the 2021West Sussex Census data on average household size of 2.4 persons per household) which would take the demand curve well above the top of the chart by 2040 and beyond.

So one must ask how HDC and Southern Water have now suddenly decided that there will be sufficient new water sources to supply existing demand plus the scale of new building  which the government wishes to impose on the district and, on top of this huge new demand, to make up for the 20% reduction in the current supply source at Hardham which Southern Water conceded as part of the deal to scrap Water Neutrality. 

Although HDC jointly commissioned the 2022 independent water consultants review, its approach to assessment of water demand is purely theoretical and it has no interest in assessing actual water consumption when considering development applications. All an applicant has to do is submit a calculation showing that if occupiers limit wc daily use, showers, baths, car washing, garden watering and other domestic water use then in theory they might only use 110 L per day per person and the application will be approved. But the reality is that when occupied, actual water consumption will be considerably higher as the recent Southern Water actual use data reveals. But HDC’s answer to this flawed approach is that it does not matter what actual (rather than theoretical) water use is, Southern Water has an obligation to supply so it is not HDC’s problem. In other words, a total abdication from responsibility for the consequences of it flawed policy and blinkered approach.

So what is Southern Water saying about this? As the table above shows, back in 2022 Southern Water was flagging up that even with the then theoretical 85 L per day per person Water Neutrality target for new development, there would be a supply/demand deficit increasing year on year up to 2040. Applying the post Water Neutrality HDC requirement of 110L per day per person, the supply shortfall would be considerably more significant. But if you substitute actual water use figures for the HDC theoretical ones then the shortfall will go off the top of the graph.

Months ago the Environment Agency warned of impending drought conditions in the south east.

And Southern Water has sent no less than three messages to customers in May alone flagging up serious water shortage concerns and its ability to “keep taps running”.

“Water scarcity is real and it’s happening on our doorstep”  - 7 May 2026

“As soon as 2030 water demand could exceed supply”  - 7 May 2026

These serious concerns reflect the data Southern Water supplied to the independent water consultants back in 2022 and would have been known about by Southern Water long before then. Yet only now they tell us that while they will continue to fix leaks the water will run out unless we use it less.

They say they are building a new reservoir but that is not in the SNWRZ and will serve Hampshire and the Isle of Wight.

They say they are upgrading the Hardham aquifer site (the principal supply for SNWRZ/Horsham District) but they have already agreed to cap abstraction at over 20% less than previously from that site going forward as part of the deal with the Government to scrap Water Neutrality.

And what of our MP who made a showboating speech in Parliament about the water supply issues? Fine words but we have seen no actions since. Perhaps unsurprising since it was his plan when he was on HDC to target Southwater for “at least” 1000 new homes. He has been aware of the water concern for many years – he dismissed it when SRS raised it with him when he was on HDC and has not responded to written requests from SRS since he was elected to Parliament.

Two years ago 20,000 homes in the Horsham District (including in Southwater) were without water for some days. Residents will recall queuing for bottled water supplies. This has been recently mirrored in Tonbridge and in North Kent (Whitstable). A very likely foretaste of what we have to come.

There are three imperatives.

Firstly, HDC Planning must be entirely satisfied ,when reviewing and approving new development applications, that there is secure and sustainable water supply to meet existing demands in the district and for the additional demand from new development. Their primary responsibility and duty is to the residents in their districts and they cannot just sit back and rubberstamp new development applications on the basis that they have to do what the Government tells them to. To do so is unquestionably negligent, and constitutes maladministration.

Secondly, it is incumbent on Horsham’s MP to step up to the plate and fight for the interests of his constituents. If he is not prepared to do so then one has to question what use or purpose does he serve. At least the Member for Whitstable had the initiative  and drive to speak out and call for a moratium on new housebuilding (other than social housing) in his constituency until the east Kent water supply issues have been permanently resolved.

Thirdly, Southern Water must be transparent and up front about how they will be able to supply the existing SNWRZ water supply demand and the demand from the tens of thousands of new homes already approved or to be approved under the Governments plans to continue covering the SNWRZ with new homes. Leak fixing and telling people to use less water alone does not cut it. ISouthern Water knows that major new supply sources are long overdue (due to lack of investment) and are the only way the huge increase in demand can be met. Unlike the water it is pumping into our rivers and harbours, they must come clean.