(ecoafrica.com)  

  (Wikipedia.org)

The picture above is of the Palmiet River and on the bottom the Crocodile River in Mpumalanga. Notice the difference in colour which is indicative of different chemical characteristics.

 This system incorporates the assessment of biota (living organisms) in rivers as a method of determining the condition or “health” of a river. Aquatic benthic macroinvertebrates (water insects that live on the riverbed) in particular, are recognised as valuable organisms for bioassessments. This is largely due to their visibility to the naked eye, ease of identification and rapid seasonal life cycle. For each genus of aquatic insects a score/number has been assigned to them, with the score being higher for those insects more susceptible to chemical changes in the river. Therefore, a high SASS score for a river is correlated to good water quality or a “healthy” river.

 (watermonitoring.uwex.edu)    

 (ecologyadventure.edublogs.org)

Above is a picture of a dragonfly larva and at the bottom a stonefly nymph. The dragonfly larva is fairly common and can withstand substantial changes to a river, while the stonefly nymph is very sensitive to changes in the water and therefore has a high SASS score attached to it.

A potential problem for this method may arise in a situation where a stream or river flows through an urbanised landscape. Within these landscapes the habitat of a river, both in-stream and riparian is often altered, degraded or quite simply lost through development. This in turn may result the composition of insect communities, as available habitat can be one of the most limiting factors affecting aquatic insect communities. Therefore, if one were to use SASS to evaluate and monitor the health of a river in an urban landscape, it is not always easy to determine whether the absence of certain aquatic insects is due to poor water quality or due to loss of habitat.

It is without exception that rivers flowing through an urban landscape are poorer, in terms of biodiversity, than rivers flowing through a natural landscape and can therefore be considered as comparatively unhealthy. However, it is important to recognise that an urban river may possess good water quality without the presence of particular aquatic invertebrates.

Another impact arises out of the fact that rivers in the Western Cape are known as systems with low productivity because of the nature of the soil and the indigenous vegetation. What this means, is that our native vegetation is slow growing and drop leaves at a constant rate throughout the year. Alien trees on the other hand produce vast quantities of leaves on a seasonal basis (those of you who have to take the rake out in autumn will know what I mean). For the trees along the river, the majority of their leaves fall into the flowing waters of the river. This creates a problem for all the aquatic animals in the river that eat the leaves (from tiny aquatic insects to crabs). The river becomes overloaded with all the leaves in one season and so the shredders (aquatic animals that tear up and eat the leaves in a river) cannot clean the river of all decaying organic material. The increase in leaf litter helps to create a deeper silt layer and increases the nutrients available in the river, both of which the natural flora and fauna are not used to, and so the aliens trees are able to further out compete the natural plants as they thrive in nutrient rich environments.

Cape River Crab pictured in the river at Paradise Park

Along a river system it is healthy to have patches of sun and shade as different aquatic insects require differing amounts of both, in the water and along the banks. Unfortunately because many alien trees have the ability to completely overrun an area (a good example would be the Poplar Tree) they create large areas of shade along the river. This affects many of the aquatic insects that require sun. For example dragonflies love to bask in the sun and studies have shown, that by removing big alien trees in river systems helps to increase the amount of different species of dragonflies along the river. This is very important as we often use aquatic invertebrates to determine the health of a river and if they are absent from a river system we may wrongly presume it is because of the water quality, when it is in fact actually because they do not have the right habitat available.

The system of using aquatic invertebrates is called SASS (South African Scoring System) and I will put an article about the way it works next week. I hope this little piece of information has broadened your understanding of why we are constantly looking to remove alien trees along our river, and if you have any questions or comments please feel free to contact me (jason@fol.org.za).

See you on the river,

Jason

Liesbeek River Project Manager

CONTACT PERSONS AND NUMBERS

• Liesbeek Maintenance Project: Jason 0846618264; info@fol.org.za or secretary@fol.org.za; Ntobeko 0710419424.
• Water Pollution: Brian February (Bishopscourt to N2 Mowbray) 0216841077/0834688243
  Johan Marthinus (N2 to Table Bay) 0842995595
• Displaced Peoples Unit:  Wayne.Aldridge@capetown.gov.za
• Environmental Standby & Emergency (24/7): 0834 99 1717
• Environmental Law Enforcement: David Morris or Vaughan Thompson 0217130510
• Centre for Environmental Rights: 021 4471647
• CITY CALL CENTRE City Complaints, repairs etc:  contactUS@capetown.gov.za 0860 103089, SMS 31373 160 characters maximum. Get a reference tracking number.
• ROADS & STORMWATER (Potholes, flooded roads and chemical or other spills) Telephone: 0860 103054 Postal address: PO Box X1694, Cape Town, 8000 E-mail: watertoc@capetown.gov.za
• WATER & SANITATION (Emergencies such as leaks, burst pipes, sewer defects/blockages and complaints e.g. low water pressure and water wastage) Telephone (Account & consumption) queries: 0860 103 089 Fax: 021 957 4726 E-mail: watertoc@capetown.gov.za Website: www.capetown.gov.za/en/water

• SOLID WASTE (Illegal dumping, wheelie bins, cleansing, extra cleaning) Postal address: PO Box 298, Cape Town, 8000 Telephone: 0860 103089 Fax: 0860 103090/021 4004302 E-mail: wastewise@capetown.gov.za Website: www.capetown.gov.za/en/solidwaste
• CITY PARKS: www.capetown.gov.za/en/Parks
• BIODIVERSITY MANAGEMENT BRANCH: www.capetown.gov.za/biodiversitymanagement
• ENVIROWORKS: Biannual newsletter. Environmental Resource Management Department, City of Cape Town, 44 Wale Street, Cape Town 8001 PO Box 16548, Vlaeberg 8018 • Tel: 021 4872284 • Fax: 021 4872255 •E-mail: enviroworks@capetown.gov.za,  Website: www.capetown.gov.za/environment

A group of individuals 20 years ago changed the course of the Liesbeeck River after the formation of the Friends of the Liesbeeck, under the auspices of the Wildlife and Environment Society of South Africa (WESSA).

“Our founder members met with the intention of raising awareness of the value of the Liesbeeck River, with a long-term vision of a restored river and its surrounding environment,” says secretary of the Friends group, Francine Becker.

The original committee members of this Friends group, which in time inspired similar groups for other rivers, were Peter Price, Bonita Bezuidenhout, Evan Duguid, Edward Tilanus and David Wheeler.

Ms Becker wants members of the public to help celebrate the group’s 20th anniversary by contributing photos, stories, poems and newspaper clippings or anecdotes about the river or the Friends group.

“We want to set up a display on the anniversary of the founding meeting of the Friends of the Liesbeeck, Monday November 28 – so all contributions should come in.

“The first activities of the Friends involved river walks and talks, some for historical interest and others for bird watching and gaining a general understanding of the river.

“Today our main activities have broadened to include collaboration with universities and other research institutions, but we still provide information by means of guided river walks, newsletters, campaigns and exhibitions, and river signage,” says Ms Becker.

“We lobby and network for best management practice of all rivers, and as our contribution, run the Liesbeeck Maintenance Project.”

The group organises activities and audited clean-ups on the river, usually with the help of students and interns and is concerned about pollution, litter and dumping, alien vegetation and erosion, illegal extraction and damming, canalisation and channelisation as well as inappropriate development, flooding and therehabilitation of the river and its surrounds.

The group believes that rivers are invaluable assets in urban settlements as they function as stormwater catchments while at the same time serving as green spaces for recreation, enjoyment and wildlife habitat.

“However, urban rivers are being degraded by erosion and silt deposits, pollution from stormwater runoff and industry, loss of habitat from development and engineering, and litter accumulation,” Ms Becker says.

This has been recognised by the City of Cape Town in the launch of the integrated catchment management plan in memory of Professor Kader Asmal, former MInister of Water Affairs and Forestry. “The proposed intervention addresses an urgent need to improve fresh water ecosystem health and functions, and is a welcome expansion of the work already being done by the Friends of the Liesbeeck and other Friends groups,” says Ms Becker.

Despite many threats and its expansive urban back drop, the Liesbeeck remains the cleanest urban river in Cape Town and probably all of South Africa, Ms Becker says.

“Although impacted by urbanisation, it still retains many natural features and displays numerous qualities that often exemplify much larger rivers.”

When there is heavy rainfall, rapid torrents flow from the steep slopes of Table Mountain through Window, Skeleton and Protea gorges, then slow over the foothills near Kirstenbosch, and finally, through a series ofcanalised and non-canalised sections the river reaches the confluence of the Black River, nine kilometres from its headwaters.

The Friends’ main project is the Liesbeeck maintenance project (LMP). “This aims to ensure a litterfree Liesbeeck and a well-maintained river trail through a process that creates jobs and develops skills, improves safety, reduces anti-social behaviour and encourages sound environmental practices,” Ms Becker says.

The LMP team removes litter, cuts back overgrown vegetation, weeds, sweeps the walkway and removes graffiti.

City departments provide support by mowing and removing all waste collected as well responding to incidents of pollution reported by the Friends.

“Besides these tasks, the team has planted and watered numerous trees and groundcover and already some of these have propagated themselves, proving that the work being done is sustainable,” Ms Becker says.

The committee attributed their 20-year success to a number of fundamental tenets which they adhere to. These include:

Learning from others, making the river accessible, having a dedicated project team and partnering with City officials and councillors and getting the City to help in projects.

Building capacity and expertise and finding innovative solutions to challenges, and creating awareness. Exploring other uses of green spaces and how to manage them sustainably has been equally important,” she says.

“We would like to honour past committee members and ask that if you were a committee member or know of someone who was active in Friends in the past, post a message to: www.fol.org.za,” Ms Becker says.

You can email:
secretary@fol.org.za or
snail mail: FoL, PO Box 333, Rondebosch.

Article courtesy of Southern Suburbs Tatler, Cape Community Newspapers, Independent Newspapers (Cape)
● Information supplied by The Friends of the Liesbeeck.

Saturday 12 November, 10h00 – 13h00

The Friends of the Liesbeek will be leading our November Friends Group Workshop in celebration of their 20th anniversary!   This ‘workshop with a difference’ will begin with a slow and gentle walk-and-talk along the beautiful upper reaches of the Liesbeek River down to Paradise Park in Hiddingh/Newlands, visiting the riverine park managed by Joan Parker from the Bishopscourt Village Residents Association en route.

Notes:

Meet in the small car park on Winchester Avenue at 10h00.
Directions: From the M3, turn onto Rhodes Drive and travel towards Kirstenbosch National Botanical Garden.  Near the entrance to Kirstenbosch, turn into Kirstenbosch Drive at the Stone Cottages and Church of the Good Shepherd.  Turn first right into Winchester Avenue.

In the event of rain, please do still meet in Winchester Avenue and we will proceed as a group to the nearby Kirstenbosch Lion’s Club Hall and ’workshop’ there.

Bring along walking shoes, a hat, a windproof jacket, a liquid refreshment and a picnic lunch.

Return transport will be available back up to the car park for drivers and those needing it.

Please RSVP to Sandy by Friday 11 November:  call 021 701 1397 or e-mail admin@wessa.co.za

Project to clean up city rivers gets afloat

Babalo Ndenze

Metro Writer

THE city council has employed 400 people to clean 14 of its most polluted rivers as part of a programme named after the late ANC stalwart Kader Asmal.

Yesterday mayor Patricia de Lille announced the river cleaning programme in honour of Asmal, who first identified the need for such an initiative to ensure a clean water supply.

The announcement was attended by Asmal’s widow, Louise.

The river cleaning is to be part of the Mayor’s Special Job Creation Project, announced by De Lille last month. Read the full article City River Project

What do you think?

See FoL committee member Kevin Winter’s response below.

Kevin Winter responds:

The Editor

Cape Times

Dear Sir / Madam

Cleaning up the City’s rivers

The Friends of the Liesbeek welcomes the Mayor’s announcement to establish a river cleaning programme (Thursday 20 October). It’s about time! Citizens, whether living in the leafy suburbs or polluted canals in Khayalitsha, are desperate for a breath of fresh political will to address decades of abuse and neglect of the City’s waterways. This kind of programme deserves broad support. We want to see a host of ‘willing to work’ people safely removing years of accumulated litter and discarded junk that fills our rivers. A clean-up will definitely help, but it will also be an exercise in futility if the root cause of the problem is not addressed. The really hard nut to crack lies in water quality and quantity. Bad planning and ineffective management have altered our catchments and left rivers with flows that are putrid in summer and scary in winter. If the programme is to do credit to Kadar Asmal’s thinking and approach to water resource management, then it needs to address these difficult issues too.

Over the last 20 years the Friends of the Liesbeek have been trying to do exactly what this programme is proposing: cleaning, planting and improving the river, and much more. It therefore came as a surprise to us that the City intends to introduce a programme that even includes the Liesbeek. The consultation is missing, but hopefully not lost. We can show how our Maintenance Project involves a planned and supervised activity operating in a complex river environment, and includes efforts to contribute to the skills and capacity of the workers on the team. We hope that the initiative will strengthen our existing programme rather than compete against the good work that has been done over many years.

Kevin Winter

Friends of the Liesbeek

After a dry winter we wonder what spring and summer have in store for us! Perhaps all of us should look again at being waterwise in our homes and gardens. However, we still can enjoy the display nature puts on -  see the lovely photos of flowering plants to be found in our area in the latest newsletter September 2011 Newsletter.

IMPORTANT!!! This year we are celebrating the 20^th anniversary of the Friends of the Liesbeek and we are very proud to belong to such an active environmental organization. To celebrate the occasion we would like to ask all members and interested persons  to contribute photographs, poems, newspaper articles or anecdotes – be creative! Please let us have your contributions before the end of October so that we can set up a display on the anniversary of the founding meeting of FOL,

Monday 28^th November 2011.

PLEASE  HELP: We would also like to honour past committee members and ask that if you were a committee member or know of someone who was active in FOL in the past, to send us an email, post a message  on the website or call  Francine at 021 6715385 . Our email address is secretary@fol.org.za and our postal address is still P.O.Box 333, Rondebosch.

Warm regards, The Committee

In addition to the traditional categories (open, handicap and community) and the SABAP2 category for the avid committed birders/atlasers, there is also the Garden Bird category. All you need to do is spend a minimum of one uninterrupted hour of observation making a list of the birds that visit your garden.

You can do your BBD survey on 26 Nov. and/or any day during the week leading up to BBD (i.e. 19-25 Nov.). This year, all BBD Garden Bird lists will be curated through the MyBirdPatch website which will generate some valuable data to the MyBirdPatch database plus hopefully add some more active participants to the project. You can also record birds from a registered MyBirdPatch site or a new site which you may consider doing for BBD.

BirdLife South Africa have published a media release about the event – you can view it on the BLSA website (www.birdlife.org.za). Follow the link “Media Release” on the left hand menu or the link lower down on the first page.

The event is organised by the Oceans Conservancy. Some pictures follow.

Clemecia, Trev and Chester

The Plastics Federation Cleanup Crew at Lagoon Beach

We recorded the trash we picked up as best we could on the official sheet. There were really just too many pieces of plastic to count – thats why we have no food wrapper count. You will also notice hardly any plastic bottle and no glass bottle. I think this may be partially attributable to the fact that we were not the first to walk the stretch of beach and the bottles probably got picked up in the first pass!

We notice one item that was really high an not covered by the categories provided and that was what I first thought were lollipop sticks but later found to be earbud sticks! We counted both as one item although there were far more of the smaller earbud sticks.

Plastics Federation

Count Sheet

Finally here is a picture from Google Earth showing the extent of the area we collected litter from. It is about 600m and we were at it for 90 minutes or so and collected two bags of rubbish weighing a bout 20kg combined and two tyres! Bear in mind the plastic is wet and has sand adhering to it so the weight of the rubbish would be considerably less.

Location of the litter collection

For more information visit these sites

Plastics Federation

Oceans Conservancy

Another Clean-up will take place at Observatory from 9h00.

Heritage  Day 24^th September

Birdwatching at the Observatory Hide

The Friends of the Liesbeek will be meeting  on Saturday 24^th September at the gate at the South African Astronomical Observatory at 17h00 for an outing to the bird hide on the Raapenberg Wetland. We will also launch our participation in the MyBirdPatch Facebook  page. This is a virtual atlas where everyone can log on, ask questions and note the birds found in their backyards, and is coordinated by Les Underhill from the ADU at UCT. For more information see  http://mybirdpatch.adu.org.za/.