This is the story of how the lower Silvermine Wetlands came to be. Like most stories with a positive ending, many people and a good number of years were involved. And still are!  Some of the key initiating conservationists have subsequently died. Their legacy lives on for the rest of us to enjoy. Lest their names are lost too soon, this story records their actions as a thank you and a reminder of how much that is good is achieved through the energy and vision of a group of individuals committed to conservation. 

The original transformations of the Silvermine River are natural and shaped by forces far beyond the Fish Hoek Valley. Sea level rise and increased storm frequency as predicted consequences of Climate Change may once again deliver transformation from forces beyond this valley.

The previous interglacial provides a relevant geological context for the beginning of this story. At that time the Silvermine River would have flowed into the shallow sea that flooded the Fish Hoek / Noordhoek gap making an island of the tip of the Cape of Storms. By 12 000 BCE the sea had receded, and hunter gatherer communities made their home in Peers Cave. Today these artists of Skildersgatkop would battle to recognise the topographical features that form the Fish Hoek Valley. The contours of the vast dune fields that swept from the sea to encircle Skildersgatkop and Peers hill are all but invisible under roads, buildings and dune colonising vegetation.  The river would have been a silver skein meandering through the sand to enter the sea almost in the middle of Fish Hoek bay.  In summer, shallow restio lined ponds formed in the river’s meanders through the dune slacks.

Fish Hoek Valley circa 1940 Solomons photo archive

Lower Silvermine river Circa 1940 Solomons Archive.

Note the barrier on the Fish Hoek side which attempted to confine the Silvermine River to the Clovelly side and to stop flooding into Fish Hoek.

Lower Silvermine river. Photo supplied by Lewis Walter -origin unknown

Today the Silvermine River flows through a green corridor pressed against the foot of the Clovelly mountains. This green corridor is home to hundreds of species of birds, reptiles and animals. “A 12.3km life support system for ‘ten thousand things’, in the words of  local conservationist Tom Keane. 

1979 Photo of Silvermine River from the CSIR Estuaries of the Cape Report

The Silvermine River Society picks up the challenge to Rewild the river

The story of how the Lower Silvermine Wetlands came to be started when a few locals who hacked out Australian acacias in the river greenbelt formed the Silvermine River Society (SRS) in 1985.  Lewis Walter the chairperson of the SRS recalls how a public meeting was held under the the auspices of the Cape Peninsula Conservation Trust to discuss the growing threats of urbanisation to the Silvermine River and the Skildergatskop Sand Dunes. Key speakers included Professor John and Mrs Grindley of U.C.T’s Environmental and Geographical Sciences Dept, and Mr. Tom Keane, well-known Fish Hoek conservationist. The meeting concluded with the formation of the Silvermine River Society.  Concerned about the degrading state of the river resulting from invasive alien vegetation, littering, illegal dumping and homeless people living and making fires, the SRS started lobbying for the `rewilding’ of the section flowing between Fish Hoek and Clovelly.

The SRS’s vision was to rehabilitate the lower reaches of the Silvermine River and to establish a Source to Sea Hiking Trail. At that time, the river had been reduced a canal lined with invasive kikuyu grass and Port Jackson (PJ) thicket. A scattering of hardy indigenous shrubs and restios struggled for space.  In earlier decades, the southern bank had been reinforced with a rubble berm to keep the river lined up with the Main Road and Railway bridges.  Subsequently the river course was straightened so that storm water could rush unimpeded to the sea.  Every few years the Cape Town municipality would use a bulldozer to open and straighten the canal.

The Lower Silvermine River in 1992 in its sand canal

In the early days of the SRS the focus was on removing the alien vegetation and litter from the river corridor and opening a hiking path from the beach to the Sunbird Centre. The SRS hosted monthly Saturday afternoon hacks.  Tom Keane of the long established Fish Hoek Alien Vegetation Control Group, fondly called the Mountain Weeders was the head hacker. Lewis Walter, chairman of the SRS, his wife Jean and their alsatian, Jim and Thelma Langridge, Hannetjie Allen, Eric Barnes the Clovelly bird expert and Jack Fudge formed the core of the hacking group. Younger members Mike Silberbauer, a fresh water ecologist, and Chris and Kim Kruyshaar joined the hacks and became increasingly involved in calls for ecological management of the river.

Photo of Lewis Walter in orange shirt and Tom Keane in front

Photo  on the RHS shows the extent of the Port Jackson (PJ) thicket. Tom and his Mountain Weeders won an award for successfully eradicating the PJ and Rooikranz acacias on Elsies Peak. Tom wrote a column for the False Bay Echo in which he showcased the flowers in season on Elsies Peak and along the river.  His post of 10th August 1988 Conservation – the Cutting Edge clearly reflects his passion for environmental rehabilitation. “Cheese and Wine conservation is all very well but it doesn’t improve the environment, it does not remove the alien vegetation. To cut the aliens down, to clean the river – this is the cutting edge. This river of ours is the only home of Xenopus Gilli, the endangered Cape Platanna. It is a 12.3km life support system for ‘ten thousand things’.  Who degraded it- Man! Who can upgrade it – Man!  That means us the people of the Valley.”

A man of foresight, Tom was in regular contact with the Plant Pathology Research Institute at Stellenbosch University. When the Institute was looking for a test site to release the biological control agent for Port Jackson, Tom offered to release the spores of the gall forming rust fungus Uromycladium tepperianum along the Silvermine River.

FH Mnt Weeders awarded in 1991

He spent months inoculating PJs with Uromycladium spores and incubating the inoculated plants with little silver shields.  His dedication paid off. The fungus thrived and continues to spread to new PJ plants to this day. It weakens them so that  even if they don’t die, they flower  less and produce far less seed.

Source to Sea Silvermine Trail.

While the SRS received in principle support for the development of a Source to Sea / Coast to Catchment trail from both Fish Hoek and Cape Town municipalities, and after its promulgation, by TMNP, to date no funds nor manpower have been provided to establish the trail. The trail concept received lots of positive press coverage. It is a unique opportunity in a large metropole to hike through the full range of riverine eco-systems: from the beach, past the estuary, along the coastal floodplain with patches of reeded wetlands, up and over the toe of the remnant sand dunes around Skildersgatkop and Peers Hill to join up with an existing trail from the Silvermine Nature Reserve at the cement drift below the Sunbird Centre.

Lewis Walter was especially determined to establish the trail. A network of footpaths already criss-crossed the area. It took little persuasion to encourage the regular SRS hackers armed with loppers and bow saws to join these paths and mark a formal route.  The route was neatly marked using green spray paint and a stencil of the SRS logo, the Cape Platanna, on suitable stones and tree trunks. This well intentioned graffiti has subsequently weathered away.  In 1995 Sandy Barnes of the Friends of Silvermine Nature Reserve (FOSNA) and Kim Kruyshaar (SRS) teamed up to produce a map and route description to promote the hike.  Along the route was an especially beautiful area opposite the golf course where the river flowed broad and shallow under willow trees.  It had been an alien acacia and eucalyptus thicket until the SRS cleared it and planted milkwood, wild olive and wild camphor and created an outdoor classroom for the local schools. Called, The Glade it was discovered in the early 2000s by homeless people who built shacks and moved it. It took years for the authorities to negotiate to relocate the illegal occupants.

Although security fears and the presence of bush dwellers has impacted the popularity of the Source to Sea Trail, the route has stood the test of time.  Each year it is formally cleared by the Riverine Rovers* for their annual Source to Sea fund raising hike. Terry Rothwell has organised and lead this walk since about 2011 (*The SRS was reconstituted as the Riverine Rovers under FOSNA in 1995. In about 2004 Terry Rothwell took over as chairman from Lewis Walter and Evanne Rothwell as secretary and environmental educator.)

Sadly, defending the Source to Sea trail is an ongoing battle. TMNParks does not have a regular maintenance programme for the section of trail on their land. Downstream, both trail and riverine wildlife are threatened by the proposed FH By-pass expressway. If built this road will pave large sections of the remaining river corridor and dislocate the river from Fish Hoek. In addition, and without public consultation, the City sold a section of land upstream of the Carlton Road / Pipe Bridge footpath for housing development in an area where the river corridor is especially narrow. Inappropriate development abutting and within the river corridor is an ongoing threat to its ecological integrity. These challenges are not new to the local conservationists and especially the Riverine Rovers and FOSNA who are determined to keep the Source to Sea Trail open.

A flagship victory that should have set a precedent for conservation.

It took 19 long years to stop a private housing development on the Skildersgatkop sand dunes on land designated as Cape Peninsula Protected Natural Area. This battle deserves an account of its own, but for the sake of brevity an abridged version is provided. The battle brought conservationists together across the Far South to form the Silvermine Valley Coalition. We believed that it would set a legal precedent to stop inappropriate development. Sadly although the case was won, inappropriate development remains an ongoing threat to natural areas along the urban edge. Core members Lewis Walter and Kim Kruyshaar of SRS, Sandy Barnes of FOSNA and Andy Gubb of WESSA supported by local civics and environmental NGOs arranged numerous public meetings and briefed attorneys for two lawsuits. So strongly did Theoniel Potgieter, the coalition’s attorney, feel about the inappropriateness of the development that he offered over 100 hours of his time for free. WWF provided the funds for the deposit required by the court. After the court battles were won, WWF donated the funds to FOSNA for chainsaws and other equipment to continue their alien vegetation clearing programme. Additional funds were raised by the community through various projects. One of these was to cut pine trees in the Silvermine Nature Reserve and sell them as Christmas trees. Long Beach mall management paid handsomely for the largest that the volunteers could fit onto one of their private bakkies. Eventually it took Sandy Barnes of FOSNA searching for days through the files at Cape Nature to find the decisive condition set out by Min of Environmental Affairs, John Wiley in 1987 that no development would be permitted on the contested section of the Skildersgatkop dunes. Till then existence of such a decision had been denied by key government officials even though Min Wiley’s decision was recorded in the media. Sandy and Kim won the Cape Times Centenary Award for Conservation in 1998 for their persistent involvement. The real reward was when TMNP bought the land at conservation rates for inclusion into the National Park.

 

Early Flood Management in the lower Silvermine.

Before the promulgation of Metropolitan Cape Town, the lower Silvermine River was the boundary between the municipalities of Fish Hoek and Cape Town. This made it difficult to get commitment from either for comprehensive management of the riverine environment.  SRS correspondence submitted to both municipalities for a river management plan elicited polite replies but little action, apart from the donation of indigenous trees on Arbour day.  One of the critical points of conflict was the intrusive bulldozing of the lower section of the river before the winter rains.

1992 photo flooding at Fish Hoek Station by Lewis Walter

Historically, the lower section of Fish Hoek up to the railway station was part of the river floodplain and was prone to flooding during especially heavy rain events. The SRS challenged the authorities to find an alternative to the intrusive bulldozing of the river.  Once again, letters to the authorities drew little effective response and the SRS appealed for support to the African Wildlife Society (now the Wildlife and Environment Society of South Africa – WESSA).

 

 

The Solution – Rewilding of the lower Silvermine River as a wetland.

The area now called the Lower Silvermine River Wetlands is an ideal storm water management basin.  However it took the 1992 floods for the authorities to act.  Fish Hoek was becoming increasingly developed and the stormwater system feeding into the river was discharging ever more water. After consultation with fresh water ecologist Mike Silberbauer and engineer Jim Langridge, Kim Kruyshaar wrote a report for the SRS motivating for the large undeveloped section of river corridor below the Clovelly / Fish Hoek pipe bridge to be excavated and rehabilitated as a wetland. The advantages would be the creation of a biodiversity rich area with significant, conservation, outdoor education and recreation potential as well as a storm water detention system. The latter would reduce the risk of flooding in Fish Hoek as well as the scouring of Clovelly beach during flood events which was a threat to the railway embankment. Additionally, the privately owned land abutting the river would no longer be within the 1 in 50 no development flood zone.

SRS Wetland Concept Plan

Fish Hoek and Cape Town municipalities agreed in principle to the wetland concept but stated that they did not have the funds for implementation. There were also significant legal issues such as the huge road reserve for the Fish Hoek By-Pass which overlay both the river corridor and abutting private land. Landowners were increasing pressure on the City to buy their land or to remove the road reserve. Once Fish Hoek municipality was merged with the Cape Town municipality, engineering consultants Hill Kaplan and Scott and planning consultant Urban Dynamics were appointed to review the road reserve and the use of the abutting riverside land. These studies resulted in a reduced road reserve and clear boundaries for the parcels of private land that could be developed and what should remain public riverside open space.

On the Clovelly side, the 2.3 hectares of riverside land opposite the electricity substation was owned by Transnet. Transnet had been making informal enquiries regarding development options for the land, even though 2/3 of it was below the 1:20 year no development flood line.  Kim Kruyshaar worked as an environmental planner for the Cape Town Municipality and Lewis Walter worked as a senior clerk on the City’s Planning committee. With the City’s Planning Department’s in principle agreement that a system of storm water detention ponds would be the best use of the land, they started the lengthy process for the City to acquire the Transnet land. Initially a land exchange was considered but eventually the City bought the Transnet land.

The remaining piece in the puzzle was a tongue of riverside open space abutting Hilton Road but belonging to the Clovelly Country Club. Sometime in the early 90s the City and the Clovelly Country Club negotiated a 99year land lease exchange. The Country Club acquired the lease of a section of City riverside open space abutting the golf course upstream of the Pipe Bridge. In turn, the City is leasing the open space opposite Hilton Road. The enquiry into who owned what and where the property boundaries were in relation to the river was prompted by Steve Perrett of the FHV Residents and Rate Payers Association. Steve was a long time resident in Clovelly who had watched the river shift position over time. For this reason he argued that the original description of the property boundary as the centre of the river needed to be replaced with a cadastral boundary. This was eventually achieved and in the process the lease exchange tidied up the responsibilities for riverside open space along this section of the river. With the land ownership issues and FH Bypass resolved, planning could start for the wetland storm water system.

City of Cape Town Develops the Silvermine Wetlands

2001 photo by Steve Perrett of first Gabion pond under construction

Engineering consultants Hill, Kaplan & Scott were appointed to do the design and manage the creation of the detention ponds and gabions.  Civils 2000 was appointed to do the earthworks and landscaping consultants were involved in the revegetation with locally indigenous plants. The entire process took a number of years from 2000 to 2004 and the project won an award for its environmental sensitivity. It was an exciting time for local conservationists as the consultants held regular meetings to ensure a good understanding of the local recreation and conservation interests and issues. Members of the SRS most especially Lewis Walter and also Steve Perrett of the FHVR&R took consultants around the site showing them the otter tunnels, going through lists of indigenous plants that grew well in the area and identifying pockets of indigenous bulbs that would need to be rescued and replanted after the earth works.

Lewis Walter in the wetlands where he so loved to be

Lewis Walter rescued many of the March Lily bulbs we see in the wetlands today. He looked after them for years until they could be replanted in the new wetland park. Steve Perrett who lived in the first house on the Clovelly side of the wetlands was actively involved in advising the consultants about the river flow patterns. The main channel of the river came through his property as well as those of his upstream neighbours. They did not want to lose this asset. At their insistence, the detention pond design was modified to include a high flow choke so that the river would flow through their properties as before, but the storm flows would be diverted into the detention ponds. With his vast experience on the FHVR&RA, Steve had invaluable on site knowledge of where City services crossed the area. Services were not always where the infrastructure drawings indicated them to be, which is an obvious problem for unsuspecting bulldozer drivers.

The Lower Silvermine Wetland Biodiversity Conservation Area

Today the Lower Silvermine Wetlands are highly valued by locals and visitors alike. The footpaths are popular running and dog walking routes.  A rare bird visitor, a little crake caused much flurry and put the wetlands firmly on SA Bird Club’s list of must visit local birding sites. Schools use the wetlands as an outdoor class room, sometimes on their own and sometimes they ask the Riverine Rovers to host a programme for them.  Evanne Rothwell’s water SASS is especially popular as the students get hands on with fun and freaky water bugs. Sheila Morrison of the RRs completed a comprehensive plant list for the Wetlands, while Lewis continued with his photographic record of wetland plants.

Best of all, is the stamp of approval from the local wildlife. Otter pairs breed in the wetlands as do the endangered Western Leopard Toad. There are frequent sightings of snakes, porcupine, mongoose, duiker, etc. as well as a rich diversity of wetland birdlife. The City erected attractive information signage. The Riverine Rovers under Evanne’s management added education signs which provide information about the seasonal changes in the wetlands. Apart from educational outings on request, the Riverine Rovers also organise litter clean-ups and are involved in ongoing planting of locally indigenous plants.  The Western Cape Leopard Toad breeding season is a highlight and breeding ponds and numbers of toads are recorded each year and submitted to SANBI via the local toad co-ordinator.

A Clovelly art studio hosted a mosaic course for locals to create mosaics of some of the charismatic creatures. These have been positioned around the walk way as eco-art to celebrate the local wildlife. An educational insect inn has been built for the wetlands but has not been placed due to the Covid lockdown restrictions. Watch this space for more eco-art!

Silvermine Wetlands Eco-Art

Under Terry and Evanne’s stewardship the RRs small team has made a significant contribution to enhanced management of the wetlands and maintained pressure on the authorities to deal with the threats.  The RRs took over the responsibility of employing a River Warden when the City funding was not renewed.  Elvis Fanele, the current River Warden. works once a week and does invaluable work removing alien vegetation, litter and keeping the paths from being overgrown.  Minor repairs to the benches and bridges are carried out by RR members. Bigger repairs are reported to the relevant City staff.

Today the biggest threats to the wetlands are: 

1        The all too frequent sewerage spills from storm water pipes feeding into the wetlands which has a serious negative impact on the water quality. ESKOM load shedding has increased the frequency of the shitload into the river.   Lewis was meticulous about reporting, recording and challenging the unacceptable sewerage design that results in the spills. Lewis died in October 2019, but he would be heartened by the pressure the RR and the FHVR&R are increasing on the City to upgrade the sewerage pump system to stop the spills.

2        The rate of Typha growth and siltation of the wetlands. Typha growth is accelerated by the sewerage spills. Dominance by Typha reduces the open water area and the biodiversity of the wetlands.  It is also a potential fire hazard especially for the wooden walkways and bridges. The City’s periodic dredging and cutting of Typha is too infrequent to address the problem

3        Homeless people sleeping in the wetlands and under the bridges, without toilet or refuse facilities, leave a considerable mess, most especially at the estuary. The City does not attend to the issue of illegal sleeping in the area nor the mess and litter without a huge amount of pressure.

Positive changes in local authority’s attitude to the lower Silvermine river.

As a river flowing through an urban environment, the lower Silvermine still faces serious pollution challenges and potential development threats. However, the City’s investment in a biodiverse wetland storm water system when a series of grassy detention ponds would have been far cheaper to build and maintain reflects a distinct turning point. In August 2010 the wetlands were proclaimed as a Bio-diversity Agreement site.  The City drafted a management plan with input from the RRs, which is in the process of being finalised.  A conservation staff member, currently the enthusiastic and committed Fay Howa, was allocated to interact with the Riverine Rovers about management of the wetlands.

The 2017 – 18 Day Zero Drought raised the profile of urban water sources and specifically the valuable environmental services that healthy rivers provide to its citizens.  In recognition of this, the City of Cape Town initiated the liveable urban waterways programme aimed at enhancing the City’s natural waterways through partnerships with local communities.  Case studies of positive examples of liveable urban waterways are being compiled. The City has identified the Silvermine Wetlands as “a wonderful example and is perhaps the seminal example in Cape Town of a liveable urban waterway”

The old guard of the SRS, Tom Keane, Jim Langridge, Jack Fudge, Hannetjie Allen, Steve Perrett and Lewis Walter all of whom have now died left a legacy that continues to inspire local conservation initiatives. Their vision and endeavours for the rewilding and rehabilitation of the river are being taken seriously by the authorities and are enjoyed by the local community both the humans and the wild neighbours.

In their memory by Kim Kruyshaar 20 September 2020