However, the dashboard data is not the whole picture when it comes Knysna's water security. There is another question that needs answering besides how efficiently the municipal system is working which is: how secure is the water source that the municipality is drawing from, namely the Knysna River, which is the towns main water supply.

This is where our Knysna River Risk Monitor continues to play a critical role.

We designed the river risk monitor to enable us to assess the river itself. It uses river-level data from the DWS to track changes in river conditions and provide an early warning indication of changing raw-water support from the river.

Here is the latest data from the river risk monitor

This is an independent assessment of data that is currently not available in the Water Tower Dashboard.

For example, today's river data indicates that a river flow of 110.6 ML/day was recorded at the Charlesford river gauge. Based on the extraction threshold used by our model, this translates to an estimated 44.2 ML/day extraction rate being available at the Charlesford extraction site. This does not mean that is how much water is actually being extracted - the last data from the municipality was ~16 ML/day. What it does do is give us an independent look at the river's capacity to support abstraction under current conditions.

The two systems, the new Water Tower Dashboard and our Risk River Monitor, serve different purposes.

• The Digital Water Tower tells us what is happening within the municipal water system
• The River Risk Monitor tells us what is happening to the river that is supporting that system

For genuine water security monitoring we need both since we need to be able to identify changes in the raw-water source even when the municipal system may still appear healthy.

Today the River Risk Monitor is returning Stable but Fragile because while river flow remains healthy, the flow trend is weakening. This is precisely what an early-warning system should do, in other words identify a developing change while there is still time to respond.

a new city-level climate intelligence platform combining our high-resolution observational record with forward-looking warming projections for more than 8,000 locations worldwide

Fortunately for us on the Garden Route they cover Knysna, Oudtshoorn, Mossel Bay and Plettenberg Bay (but no George, which is interesting.)

Let's take a look at Knysna's data because it tells a rather alarming story:

The data demands attention

In 2025, Knysna’s climate story is one of rapid change and some unsettling surprises. According to Berkeley Earth’s data, the town’s 20-year average temperature already reached 17.79°C in 2025, a temperature that was not expected until 2030. Just a few years ago, projections suggested that Knysna’s 20-year average would rise from 16.16°C to 17.75°C by the end of the decade. Yet, in 2025, with the 20-year average already at 17.79°C, the annual temperature for the year hit 18.04°C.

This means Knysna has not only met but exceeded its 2030 temperature projection five years ahead of schedule.

The SSP3-7.0 scenario, a high-emissions pathway used by climate scientists, projected Knysna’s temperature to be 17.62°C in 2025 (observed 20-year average 17.92ºC). The reality is stark: actual temperatures are already higher than this high-emission scenario estimate.

This is a wake-up call, signaling that local warming is accelerating faster than even the most pessimistic models anticipated.

What does a warmer Knysna actually mean

An increase of 1.6°C in the long-term average may not sound particularly dramatic. After all, temperatures often change by more than that between sunrise and lunchtime, for example today July 1, 2026 the temperatures ranges between 9ºC (min) and 15ºC (max) a 6ºC difference. Climate change, however, is not about the weather on any particular day. It is about shifting the baseline from which all weather occurs.

A warmer atmosphere can hold more moisture, increasing the potential for intense rainfall when storms develop. Higher temperatures also increase evaporation from soils, rivers and dams, making dry periods more severe. During hot, dry and windy conditions, vegetation dries out more quickly, increasing the likelihood that wildfires become more intense and spread more rapidly.

A temperature rise of this magnitude is not just a statistical anomaly, it has real, tangible consequences for the environment.

Ecosystems that have evolved over millennia to thrive in Knysna’s mild climate are now facing unprecedented stress. Species that cannot adapt or migrate quickly enough will likely decline or disappear, disrupting food chains and reducing biodiversity. For a region known for its rich natural heritage, including the Knysna estuary and its unique surrounding coastal forests, this is a direct threat to ecological stability.

Human health is another critical area of concern. These rising temperatures increase the risk of heat-related illnesses, particularly for vulnerable populations such as the elderly and outdoor workers. Additionally we know, as is being witnessed elsewhere, that warmer conditions can expand the range of disease-carrying insects, (eg. mosquitoes) potentially introducing new health risks to the region.

The broader implications

Knysna’s situation is a microcosm of a global trend: climate change is happening faster than predicted. While the global average temperature (land & ocean) is now at about 1.5ºC above the preindustrial average, local realities, like the one in Knysna, often outpace the global temperature averages.

The fact that Knysna’s temperatures are already surpassing projections underscores the urgency of both mitigation (reducing greenhouse gas emissions wherever possible) and adaptation (preparing for the inevitable changes). The data is a clear signal that "business as usual" is no longer an option. Local governments, businesses, and communities must come together to address this challenge head-on. This means investing in climate-resilient infrastructure, promoting sustainable land use practices, and supporting research and monitoring to better understand and respond to local climate trends.

For individuals, the message is equally urgent. Reducing personal carbon footprints, supporting local sustainability initiatives, and advocating for stronger climate policies can all contribute to a collective effort to slow the rate of change. The time to act is now before the gap between projections and reality widens even further.

We have the solutions we just need to implement them and if we don't well then the results of not doing so are on us.

The Berkeley Earth projection graph above is based on one possible emissions scenario known as SSP3-7.0. This projection should not be interpreted as a prediction of exactly what will happen. Instead, it illustrates how temperatures could evolve if greenhouse gas emissions remain relatively high throughout this century. We have lower emissions pathways available to us, but we must actively choose them!

As a result of all the above, it is clear that we are committed to a certain level of heating, to which we need to adapt. What do we need to do? My suggestion is everyone should read and take this document seriously. The adaptation research has been done. We now urgently need to implement the suggestions.

Understanding this is particularly important as the new ENSO forecasts begin pointing toward the possibility of a very strong El Niño developing later in the year.

The current ENSO state remains neutral, but the forecast envelope now includes the real potential for a very strong El Niño by late spring and summer. The multi-model median for November is +2.47ºC relative to the tropical mean, which would place the developing event in very strong territory if realised.

For Knysna, this does not automatically mean drought. The southern Cape does not respond to ENSO as directly as South Africa’s summer rainfall regions. But strong El Niño events have altered circulation patterns, rainfall distribution and the persistence of dry periods in this region in the past. More importantly, a very strong El Niño increases risk in systems that already have very little breathing room, like the one in Knysna.

Akkerkloof is critically important

The recent flood event showed exactly why the dam matters. During widespread electricity failures and operational disruptions at Charlesford, Akkerkloof effectively became the system’s emergency reserve. Storage rose temporarily during the heavy rainfall event, climbing from roughly 21.6% to 25.1%, but much of that gain disappeared within days as the system relied heavily on stored water while pumping infrastructure recovered.

By May 14, Akkerkloof had already fallen back to 22.5%. That trajectory tells an important story.

Despite one of the largest rainfall events seen in years, the system still struggled to convert the abundant water availability into storage recovery. The rivers were carrying extraordinary volumes of water during the storm, but operational disruptions limited the ability to fully utilise those river flows. Generator failures, abstraction interruptions, damaged monitoring systems and unstable pumping capacity became the major constraints.

In other words, the limiting factor was infrastructure reliability.

The coming winter matters

The next few months are likely the best opportunity Knysna will have to rebuild the dam's reserves before the higher-risk late 2026 period arrives. If Akkerkloof remains near current levels while river flows weaken later in the year, the system will be exposed to supply shocks, infrastructure failures and prolonged dry spells.

Here is the latest IRI Multi-Model Probability Forecast for precipitation for the period Spetember-October-November 2026:

By the time we get to these months Akkerkloof should ideally be at capacity as the probability forecast shows below normal rainfall in areas surrounding Knysna.

It's not just about filling Akkerkloof of course.

The extreme precipitation event demonstrated that resilience depends on several interconnected systems functioning together:

• Reliable river abstraction at Charlesford
• Functional pumps and backup power
• The ability to transfer surplus water into storage
• Operational flexibility during extreme weather
• Monitoring systems that remain online during crises

The municipality’s ongoing pump refurbishment and groundwater work are all very important. These projects will help improve the system’s ability to manage water more effectively and maintain continuity during disruptive periods. But they do not remove the underlying dependence on healthy river flows and sufficient reserve storage.

Akkerkloof is central to the town's resilience story.

Given the very strong El Niño likelihood, this coming winter recharge season is likely to become one of the most important windows Knysna has had in years to rebuild storage before a more difficult climate phase emerges later in 2026 and early 2027.

Let's hope they do everything humanly possible to use every opportunity to increase Akkerkloof storage!

Resilience in a water system

A resilient system is not one that never comes under pressure but it is one that can absorb shocks, continue functioning and recover before critical thresholds are crossed.

That is where the graphic above becomes useful.

The “business as usual” pathway illustrates what can happen when a system lacks sufficient resilience to absorb an extreme event. Once that tipping point is crossed, recovery becomes incomplete and the system settles into a lower long-term level of functionality resulting in permanent loss.

The “built resilience” pathway still experiences the same extreme event, but the system has enough flexibility and buffering capacity to recover without permanent loss of function.

This is increasingly relevant to Knysna

The municipality’s current interventions appear focused on exactly these resilience-building measures:

• improving pumping reliability
• strengthening transfer capacity
• diversifying supply through groundwater
• reducing non-revenue water losses
• improving operational flexibility within the network

None of these remove the town’s dependence on healthy river inflows and sustained rainfall. The Knysna system remains heavily reliant on surface water abstraction from the Knysna and Gouna rivers, supported by smaller augmentation sources and storage buffers like Akkerkloof.

But these upgrades will still make a major difference.

A more resilient system is better able to:

• capture water during high-flow periods (like the current one)
• reduce avoidable losses
• maintain supply during outages
• recover storage more effectively
• and continue operating through periods of stress without cascading failure

Recent data has clearly shown how the town has been operating within relatively narrow margins. Storage levels have continued declining while raw water input trends lower, and operational limitations at Charlesford appear to have reduced the system’s ability to fully capture available river flows during some periods.

This does indicate that the importance of built resilience is growing.

The current work underway should help widen the margin between normal operating pressure and a much more serious system failure scenario. In practical terms, the goal is not to eliminate drought risk entirely as that, in practice is not possible, but rather to improve the town’s ability to withstand difficult periods without crossing into long-term instability or permanent loss of functionality.

This is what resilience-building looks like in practice!

Taken together, this is a significant operational push. But it’s important to understand what these changes actually do.

They improve how the system works. They do not materially increase how much water is available.

What is improving

The refurbishment of pump stations is one of the most important elements. Knysna relies heavily on pumping water from rivers into off-channel storage like Akkerkloof. If pumps are unreliable or underperforming, high-flow periods can pass without being fully captured.

Improving pumping reliability increases the chances of storing water when the river allows it. That is critical in a system where timing matters.

The planned connection between the treatment works balancing dam and Akkerkloof should also improve flexibility. Being able to move water more efficiently within the system helps manage short-term imbalances between supply and demand.

Groundwater is another useful addition. Rehabilitation of existing boreholes and testing of new ones can provide a steady, if limited, supplementary supply. This acts as a buffer, especially during periods when river abstraction is compromised.

Efforts to install meters and reduce losses also matter. When total demand sits close to system capacity, which it does at present, even small reductions in losses or consumption can create meaningful breathing room.

What is not changing

The core structure of the system remains the same.

Knysna’s water supply is still built around a combination of river abstraction and smaller supporting sources. The Knysna River is the dominant source, supported by the Gouna River and Glebe Dam, with additional input from springs, boreholes and a small desalination plant, which is currently not operational.

Together, these sources have a combined licensed capacity of roughly 12–13 ML/day when averaged over a year. In practice, that supply is variable because river abstraction is determined by flow conditions and legal limits.

All surface water is treated through a central water treatment works before being distributed into the network.

This matters because it highlights a key constraint:

the system is not short of infrastructure alone, it is operating within defined supply limits that depend heavily on river conditions.

None of the current interventions materially increase these limits. They improve how effectively water can be captured, treated and distributed, but they do not create a new large-scale source of supply. In practical terms, demand already sits close to the system’s licensed supply range, which is why even small changes in river flow or demand can have a noticeable impact.

What this means in practice

The upgrades outlined in the statements should lead to a more stable system:

• fewer missed opportunities to capture water during high flows
• more consistent operation of key infrastructure
• slightly greater contribution from secondary sources
• better control over demand and losses

But the system will still tighten if inflows decline or demand rises.

In other words, the margin improves, but the underlying dependency on available water sources does not change.

Concluding thoughts

This is all a necessary and positive step. A system that works reliably is far better than one that doesn't!

But long-term water security in Knysna will still depend on:

• sustained river flows
• effective demand management
• and continued diversification of supply

The current work strengthens the system’s ability to cope but it does not remove its vulnerability to dry conditions.

At first glance the situation appears more stable than it did several weeks ago. Akkerkloof Dam is currently sitting at just over 31%, significantly higher than the critically low levels recorded earlier in the summer. (Note: There is an error in the DWS dashboard. They indicate that Akkerkloof is at 32.4%. This should read 31.4%)

However, stabilisation does not mean the system has recovered. Current conditions reflect a carefully balanced operational system, where production, storage and consumption are being actively managed to maintain supply.

In other words, the immediate emergency phase appears to have passed, but the underlying water system remains sensitive to changes in river flow, infrastructure performance and consumption patterns.

A system moving out of emergency mode

In January the Knysna water system entered what can fairly be described as an emergency phase.

Akkerkloof Dam dropped to around 15%, and the municipality struggled to maintain stable production from several key pump stations. At the same time, river flows weakened and infrastructure failures limited the system’s ability to move available water.

During this period Gift of the Givers stepped in to assist by transporting water into town using tanker trucks. These trucks operated daily for several weeks, helping to stabilise supply while infrastructure repairs and rainfall improved conditions.

According to Gift of the Givers, tanker operations stopped on 28 February, when Akkerkloof Dam had recovered to roughly 32%.

That moment likely marks a transition point in the system: from emergency support toward normal operational management.

What the official dashboard shows

The latest DWS dashboard highlights several important trends.

Average water consumption in the Knysna system increased slightly over the past week, rising from 11,417 kilolitres per day to about 11,655 kilolitres per day. While this increase is modest, it shows that overall demand remains relatively high despite Level 4 water restrictions.

The current 7-day Knysna consumption average is ~11 ML/ day

At the same time, the dashboard indicates that production from some sources has been declining slightly. Borehole production, for example, dropped by around 106 kilolitres per day in the past week’s average.

Pump station performance has also been uneven. Charlesford and Glebe pump stations both recorded lower average outputs compared with previous weeks, highlighting how sensitive the system remains to infrastructure reliability.

But perhaps the most important signal in the dashboard appears in the combined supply chart.

The total raw water input to the system is currently showing a declining trend. In other words, the overall volume of water entering the system from rivers, boreholes and other sources is decreasing over time.

When raw water input declines while demand remains stable, the system becomes increasingly dependent on storage and careful operational management.

These fluctuations matter because the Knysna system operates with very little spare capacity.

The role of Akkerkloof Dam

Akkerkloof Dam continues to play a critical role in balancing the system.

The dashboard notes that water from Akkerkloof was used on five days during the past week, with an average supply of about 4,551 kilolitres per day. This is a significant increase compared with the previous week.

In practice this means the dam is acting as a buffer for the system. When production temporarily falls short of consumption, water can be released from storage to stabilise supply.

This is exactly how the system is designed to operate, but it also means that storage levels remain an important indicator of system health.

At roughly 31.4%, Akkerkloof is currently stable but still relatively low in the context of its total capacity.

River flow remains a key factor

Another important piece of the puzzle is the condition of the Knysna River system.

Recent river gauge readings suggest that flows have weakened again following earlier rainfall events in February. While parts of the Garden Route experienced above-average rainfall last month, river systems often respond unevenly depending on catchment conditions.

This is not unusual. Rainfall totals do not always translate into sustained river flow, particularly when catchment soils and groundwater systems are still recovering from dry conditions. When river flows weaken, the municipality must rely more heavily on pump stations, boreholes and storage to maintain supply.

This increases the system’s sensitivity to infrastructure failures or sudden changes in demand.

Monitoring the system between official updates

Municipal and national dashboards provide valuable snapshots of the Knysna water system, but these updates typically appear weekly or at irregular intervals.

Because conditions in the system can change quickly particularly when river flows fluctuate or infrastructure performance varies it is useful to monitor a few key indicators between official reports.

Three indicators are particularly helpful:

• river stage levels at the Charlesford abstraction point and at Millwood
• short-term system balance between production and consumption
• storage levels at Akkerkloof Dam

When considered together, these indicators help reveal whether the system is moving toward greater stability or beginning to experience renewed pressure.

One way to track these changes is through the Early Warning Signal dashboard, which combines these indicators into a simple "direction" signal.

🟩 Stabilising
🟨 Stable but Fragile
🟥 Pressure Increasing

The current signal indicates “Pressure Increasing.”

This does not mean the system is facing an immediate shortage. Instead, it reflects a subtle shift in underlying conditions: river flows have weakened again while overall raw water input to the system has begun to decline.

Signals like this are useful because they often highlight changes in system behaviour before those changes become visible in dam levels alone.

Stable for now, but fragile

Taken together, the data suggests that Knysna’s water system has moved out of the most acute phase of the crisis, but it remains fragile.

Emergency tanker support has ended, infrastructure repairs are underway, and the system is currently able to balance production and demand. However, that balance still depends on several factors working together: reliable pump infrastructure, stable river flows and responsible water use.

Importantly, stabilisation does not mean water is abundant.

The margin for error remains relatively small, and sustained increases in consumption or infrastructure failures will quickly place additional pressure on the system.

What to watch in the weeks ahead

Several factors will determine how stable the system remains during the coming months.

River flows in the upper catchments will continue to play an important role in supporting abstraction. Infrastructure reliability will also remain critical, as pump failures can quickly affect production levels.

Storage trends at Akkerkloof Dam will provide another important indicator of system pressure.

If production consistently exceeds demand, storage levels should gradually increase. If not, the dam will continue to act as a balancing buffer.

For now, the data suggests the system is operating in a carefully managed equilibrium.

Maintaining that balance will depend not only on infrastructure and rainfall, but also on continued responsible water use across Knysna.

These events often happen when the high tide approaches about 2 metres, especially if a small storm surge is present. It’s easy to dismiss them as an inconvenience caused by an unusually high tide. But in reality, these events are the first visible sign of long-term sea-level rise starting to interact with the local landscape.

Understanding why this happens and why it will likely happen more often in the future is important for everyone living along the estuary.

What “Sunny-Day Flooding” Means

Flooding without rain is known globally as “tidal flooding” or “sunny-day flooding.” It happens when high tide alone is enough to push water onto land.

In Knysna’s case, the estuary water level is strongly controlled by tides entering through the narrow inlet at the Knysna Heads. When the ocean tide rises, the estuary rises with it.

Many parts of the estuary shoreline including marinas, low roads, (eg. Waterfront Drive, George Rex Drive) and marsh edges sit only slightly above the high-tide level. When the tide approaches about 2 metres, water begins to overtop low edges or flow back through the drainage system.

If a small storm surge coincides with that tide, water levels can briefly rise even higher. There is an event like this forecast for the morning high tide on Saturday March 7th. A high tide of 1.87 m plus a storm surge forecast of 0.3 m resulting in a total high tide of 2.17 m.

These events are not unusual in coastal towns worldwide, but what matters is how often they happen.

Why these floods are becoming more common

Global sea level has been rising steadily for decades. Satellite measurements since 1993 show an average rise of about 3–4 millimetres per year globally, with evidence that the rate is accelerating. In some parts of the South African coast the observed rate is even higher.

Under a mid-range emissions scenario (SSP3-7.0), sea level along the south coast is projected to rise about 10–12 cm by 2030, with substantially larger increases later in the century.

Even small increases shift the threshold at which high tides begin to cause flooding. A rise of just 10 cm means that every tide is effectively 10 cm higher than it used to be. Tides that once stopped just below the flooding threshold now cross it.

This is why sunny-day flooding tends to increase gradually before permanent inundation becomes an issue.

In many coastal towns around the world from Florida to Australia the first noticeable sign of sea-level rise has been exactly this: more frequent nuisance flooding during high tides.

Why the South African south coast may feel it sooner

Along the southern Cape coast, sea-level changes are influenced not only by global warming but also by regional ocean dynamics.

The powerful Agulhas Current flows southward along the east and south coast of South Africa. Ocean currents like this affect the height of the sea surface along the coast. When the current strengthens or shifts, it can slightly raise the coastal sea level.

Satellite observations show that sea levels along parts of the South African coastline have been rising slightly faster than the global average in recent decades. A recent analysis of satellite altimetry data found coastal trends ranging from –4 to 8 mm per year, with positive trends across much of the coast and particularly along the Agulhas Bank. In some locations such as Cape Town, observed rates of about 6 mm per year are nearly double the global average.

Even a few extra centimetres over time can make a noticeable difference when tides already approach the flooding threshold.

Why Knysna is particularly sensitive

Knysna’s geography makes it especially responsive to small changes in sea level.

Three factors play a role:

1. A narrow inlet: The estuary connects to the ocean through a relatively narrow gap at the Heads. This means ocean water entering on a rising tide can temporarily accumulate in the estuary.
2. A large shallow estuary: Because the estuary is broad and shallow, small increases in water level can spread across large areas of shoreline.
3. Low-lying infrastructure: Much of the development along the estuary edge sits close to the high-tide level. Even a few centimetres of additional water can affect roads, drainage systems, and waterfront properties.

Together, these factors mean that small increases in sea level can translate into noticeable flooding events sooner than many people expect.

Here is what this could look like for Knysna by 2030.

This map from Climate Central shows land expected to fall below the level of flooding that could occur at least once per year under a mid-range emissions scenario. Low-lying parts of the estuary shoreline including areas around Thesen Island, Leisure Isle and sections of the estuary margins are particularly exposed.

The red areas indicate land that could experience annual coastal flooding by around 2030 under current projections. This does not mean these areas will be permanently underwater, but it does mean that high tides combined with modest storm surges could flood them at least once a year. In a estuary system like Knysna’s, where water levels inside the estuary closely track ocean tides entering through the Knysna Heads, even small increases in sea level can shift the threshold at which flooding begins.

What local observations are already showing

Local observations have noticed that flooding tends to occur when high tides approach around 2 metres. This kind of local observation is actually very valuable.

Scientists often identify flood thresholds by combining:

• observed flooding events
• tide levels
• local elevation data

Tracking when these thresholds are crossed over time provides one of the clearest indicators of how sea-level rise is affecting a community.

The key change to watch is not a single flood but how frequently these events occur each year.

What the future likely looks like

If sea level continues to rise at roughly the current rate, the pattern usually follows a predictable progression:

1. Rare flooding during extreme tides
2. Occasional sunny-day flooding during spring tides
3. Regular nuisance flooding several times per year
4. Frequent flooding during many high tides

Many coastal communities worldwide are already moving through this sequence.

For Knysna, the sunny-day flooding people are beginning to notice may represent the early stages of this process. None of this means Knysna is about to disappear under the sea. Sea-level rise is gradual, unfolding over decades.

But it does mean that:

• flood events will likely become more frequent
• drainage systems will need adaptation
• infrastructure planning must account for changing water levels

The earlier communities understand these changes, the easier it becomes to plan sensible responses. If you have been following tide forecasts or the coastal surge outlook from the South African Weather Service you will have already noticed how small factors combine:

• high spring tides
• wind pushing water toward the coast
• slightly lower atmospheric pressure

When these occur together, water levels can briefly exceed the estuary's natural thresholds. Monitoring these patterns over time can help the community understand how conditions are changing.

An early warning

Sunny-day flooding is not dramatic. It arrives quietly: a road briefly underwater, a storm drain bubbling, a jetty sitting lower than usual.

But in many places around the world, these small events have turned out to be the first clear signal of rising seas interacting with coastal towns.

In Knysna, those occasional high-tide floods are telling us something important: The ocean is beginning to knock on the door.

Transparency note: AI tools sometimes assist with structuring, drafting, and editing these updates. All analysis, interpretation, and final editorial judgement remain my own.

As you can see above, the results show a mixed but largely familiar pattern, and when viewed alongside monitoring results throughout 2025, they help clarify how the estuary system is behaving in the face of pollution.

Much of the estuary remains within safe limits

Several popular estuary locations recorded low E. coli levels, well within recreational guidelines.

Recent results include:

• Belvidere: 80 /100 ml
• Crabs Creek: No growth detected
• Lake Brenton: No growth detected
• The Heads: 60 /100 ml

These values fall comfortably below the recreational guideline threshold.

This pattern has also been visible across much of the 2025 monitoring, where locations such as Belvidere, Crabs Creek, Lake Brenton and The Heads consistently recorded low bacterial levels during most sampling rounds.

The reason is largely physical: the estuary benefits from strong tidal flushing, which helps dilute and move contaminants through the system.

In other words, despite pollution inputs from parts of the catchment, the estuary still retains a significant capacity to disperse contaminants.

Areas With Elevated Readings

Some locations continue to show periodic spikes above recommended recreational limits.

In the February sampling these included:

• Bollard Bay: 620 /100 ml
• Costa Sarda: 1,500 /100 ml
• Salt River: 20,000 /100 ml

The Salt River reading is particularly high, at roughly 40 times the recreational guideline.

Looking back through the 2025 monitoring data, Salt River has repeatedly recorded elevated readings—including 73,000, 330,000 and even 850,000 E. coli per 100 ml in different months.

This recurring pattern strongly suggests that a persistent contamination source exists somewhere upstream in the Salt River catchment.

The available data does not identify the exact source, but elevated E. coli levels of this magnitude are typically associated with inputs such as:

• sewage infrastructure failures (most likely)
• sewer leaks entering stormwater systems
• informal sanitation runoff
• agricultural or animal waste

Without a proper investigation, the precise source cannot be confirmed.

Stormwater culverts remain highly contaminated

Sampling of urban culverts once again shows extremely high bacterial levels.

For example, the February results recorded:

• Train Station culvert: 67,000 /100 ml
• Long Street culvert: 17,000 /100 ml
• Queen Street culvert: 11,000 /100 ml

Throughout 2025 monitoring, culverts regularly showed values ranging from thousands to millions of E. coli per 100 ml. 

This is unfortunately typical of urban stormwater drainage systems, which often collect contaminated runoff before discharging into rivers or estuaries.

Stormwater can carry:

• sewer leaks
• septic seepage
• pet and wildlife waste
• informal sanitation runoff
• other urban pollution

When rainfall occurs, these systems can deliver pulses of contaminated water into the estuary.

Reports of sewage spills in town

Every week this year many residents have reported sewage spills in streets and public areas across Knysna. While these incidents are separate from the estuary monitoring programme, they are important to acknowledge because untreated sewage presents a direct public health risk.

Raw sewage can contain high concentrations of bacteria and other pathogens. Direct contact should always be avoided, especially any standing water in streets and any contaminated areas should be reported to the municipality so they can be addressed as quickly as possible.

Urban sewage spills can also enter stormwater drainage systems, which typically discharge into rivers or the estuary. As the monitoring results consistently show there are extremely high bacterial levels in several stormwater culverts feeding into the estuary.

While the available monitoring data does not identify the exact source of this contamination, repeated sewage spills increase the risk that polluted water may eventually reach local waterways.

Health guidance for residents and visitors

When water quality exceeds recreational guidelines, it does not automatically mean the entire estuary is unsafe, but it does mean people should take basic health precautions.

The following simple measures significantly reduce risk:

Avoid Ingestion

Avoid swallowing estuary water and try to prevent water from entering the mouth, nose, or eyes, particularly in areas where elevated bacterial levels have been recorded.

Wash After Contact

Anyone who comes into contact with estuary water — especially in higher-risk areas such as the Waterfront marina or Ashmead Channel should wash thoroughly with clean potable water and soap afterward.

Avoid Entering With Open Wounds

Do not enter the water if you have open cuts, sores or fresh wounds, as these can provide direct entry points for bacteria including E. coli.

Extra Care for Vulnerable Groups

Children, elderly individuals, and people with weakened immune systems should avoid contact with the water when “not fit for recreational use” advisories are active.

These precautions are standard public health guidance for any natural water body experiencing elevated bacterial levels.

Stay safe.

• Unbilled authorised use (such as firefighting or communal taps)
• Metering inaccuracies
• Illegal connections
• And real physical losses (bursts and leaks)

Reducing NRW is essential. No water system can remain sustainable if large volumes of treated water do not generate revenue or reach intended users.

But we need to be clear about something important: NRW reform does not remove Knysna’s structural water risk.

The risk is hydrological, not just operational

Recent system data shows:

• Town consumption averaging roughly 9–12 ML/day
• Akkerkloof storage is just above 30%
• Augmentation capacity is still limited
• River levels are highly sensitive to rainfall variability

Even if NRW were reduced significantly, the system would still depend on:

• River abstraction
• Rainfall timing
• Storage buffers

Those are hydrological constraints. They do not disappear when billing improves or meters are replaced.

The critical distinction

Of course NRW reduction strengthens long-term system efficiency and resilience.

But short-term system survival depends on:

• River flow remaining above abstraction thresholds
• Akkerkloof storage not being drawn down too quickly
• Consumption remaining within safe limits

If rainfall remains below normal and river abstraction becomes difficult, storage is still the fallback and storage margins remain thin (just above 30% as mentioned.)

That is the structural exposure.

Time scales matter

Leak detection, pressure management and infrastructure upgrades are all very necessary, especially in Knysna. But they take months to years to materially reduce physical losses. Rainfall variability on the other hand is felt within days to weeks.

Those two timelines are not interchangeable. While NRW fixes improve resilience over time, it does not insulate the town from near-term water stress.

Why all this is important to understand

There is no contradiction in throwing our weight behind NRW reduction AND acknowledging that the system remains fragile.

While progress happens on the NRW front, the water security risk can still remain elevated. Both these statements can be true at the same time!

The inescapable fact is this. Knysna’s water security currently rests on four interdependent pillars:

1. River flow
2. Storage levels
3. Augmentation capacity (ie boreholes, springs etc.)
4. System efficiency (eg. NRW, consumption)

Weakness in any one pillar increases pressure on the others and improving one does not automatically stabilise the system.

The structural reality

The broader climate context matters - a lot! Rainfall inconstancy is increasing, dry spells are getting longer and river recharge events are becoming less predictable.

In this context:

• High NRW amplifies stress.
• Limited storage amplifies stress.
• River dependence amplifies stress.

Efficiency reform is 100% necessary but dependence on raw water remains the core vulnerability the town must face head on.

Understanding that distinction allows the community to support the work that must be done around NRW, while at the same time remaining realistic about risk.

This may sound pessimistic, but it is important structural literacy!

The town and its surrounds has just experienced its lowest annual rainfall in the 1979–2025 record. That is a serious data point.

But a single record low year does not automatically mean that rainfall is collapsing or that climate change has already transformed the rainfall regime. The long-term rainfall record still shows high natural variability from year to year.

So the more important question is this:

What actually turns a dry period into a true water crisis?

A recent global study on “Day Zero Drought” events, the kind of compound crisis that nearly shut down Cape Town’s taps in 2018, offers a useful framework for thinking about this.

The key insight from that research is simple but important:

Water crises are usually not caused by rainfall declines alone.
They happen when several stresses occur at the same time.

Let's translate this into what has been observed in Knysna recently.

Water risk is a compound problem

The study defines “Day Zero Drought” as a compound event—meaning multiple pressures overlap.

Those pressures include:

• Prolonged low-rainfall periods
• Reduced river flows
• Demand exceeding supply
• Reservoir storage being unable to buffer the deficit

This understanding matters a lot because annual rainfall totals on their own can hide what is really happening in the system.

A region can experience:

• No clear long-term rainfall decline
• But increasing evaporative demand due to warming
• Shorter river recovery periods
• Growing water consumption
• Infrastructure losses

And still tip into a water security crisis.

What this means in Knysna's case

Instead of asking only "is rainfall declining?" a more useful question to ask is "is the town's water system becoming more vulnerable to compound stress?"

Based on this line of questioning and observations since early November there are four pillars that determine the towns real risk

Pillar 1: Atmospheric Stress (Rainfall + Heat)

Low rainfall matters obviously, but so does any accompanying heat.

Warmer conditions increase evaporation from soils, dams, and vegetation. That means the same rainfall total today may produce less effective runoff than it did decades ago.

Even without a dramatic long-term rainfall collapse, increased evaporative demand can intensify drought stress.

Pillar 2: River Persistence

The Knysna River and its tributaries are the lifeblood of the town's water system.

What matters is not just whether rain falls, but:

• How long river flow persists after rainfall
• How quickly levels drop back to critical thresholds
• Whether baseflow survives dry spells

Rapid spike-and-collapse patterns reduce the system’s buffering ability.

Pillar 3: Supply vs Demand

A key finding in the study mentioned above is that water scarcity is often driven as much by demand as by climate.

If demand remains high while supply falls, the imbalance then obviously accelerates reservoir depletion.

In Knysna’s case, provincial briefings have highlighted extremely high non-revenue water losses (over 50%), meaning a significant portion of treated water never reaches consumers. That amplifies stress during dry periods.

A fragile supply-demand balance makes even normal variability dangerous!

Pillar 4: Storage Buffer

Reservoirs exist to provide a safety net during dry periods.

But when dry conditions persist longer than the system’s storage buffer can sustain, risks escalate rapidly.

The research shows that when drought duration exceeds reservoir resilience, acute scarcity can follow—especially if demand remains high.

So is Knysna already in a climate-driven shift?

Based on rainfall totals alone, we cannot say that a statistically significant long-term drying trend is clearly visible in the 1979–2025 data shown above.

However:

• 2025 being the driest year in the record most definitely increases the system's exposure.
• Southern Africa is identified in modelling as a hotspot for emerging compound water scarcity risks.
• Climate change is projected to increase evaporative demand and multi-year drought persistence.

What this means is that the probability of compound stress events increases as we continue to heat.

An accurate way to frame the risk

The honest, evidence-based assessment for the area is:

“Knysna’s water system is highly sensitive to extreme variability, and climate change increases the likelihood that when a dry sequence occurs, the system will struggle to cope.”

This should focus attention where it belongs: on building resilience as soon as possible.

What does building resilience look like?

If compound stress is the real risk, then Knysna's resilience depends on:

1. Reducing non-revenue water (NB)
2. Managing demand proactively (early restrictions are better than late)
3. Protecting river baseflows
4. Strengthening storage and operational flexibility
5. Planning for multi-year variability, not just annual totals

The projected climate signal does not need to show up as a dramatic rainfall collapse to increase risk. Sometimes it shows up as shorter recovery windows and thinner safety margins.

This is the conversation Knysna should be having.