This morning I will be walking the length of the Lower Diep River to Milnerton Lagoon mouth.
I will see for myself the state of the river & meet community members & officials along the way.
Start: 8AM
[Follow this Tread]
The main tributary starts in the Kasteel Mountain, North of Malmesbury. It is joined by the Mosselbank catchment which finds it’s source in Durbanville.
It used to discharge into the ocean at three mouths but now has one fixed mouth at Milnerton Lagoon.
Malibongwe Drive Bridge & the N7 is where the river enters Urban Cape Town. Once upon a time people would float grain barges into the ocean from here.
Due to agricultural abstraction this river is a now dry here.
Rivergate land invasion.
These structures are below the flood line and cannot be serviced. Nightsoil being directly discharged into the wetland. This area is unfortunately within the conservation area.
The informal settlement on the railway line drains directly into the river. There is also industrial chemical pollution through another stormwater outlet.
Lots of bird life still persist.
The Milnerton Riding School utilises the trails along the river for riding. They proactively do flood risk management.
I will be working with the to the Milnerton riding community to deepen our working relationship along the Diep River. #KnowYourRiver
Potsdam Waste Water Treatment Works
Aquatic Scientist Dr Liz Day has joined the #KnowYourRiver walk. I’m happy to see some interventions at the WWTW to protect the river.
The maturation ponds are about to be cleaned. This will significantly improve treated water quality.
Milnerton Lagoon
Most of the water here comes from Potsdam WWTW. It was nice to see a lot of bird life in the lagoon, all challenges considered.
There’s a lot of work to do in this catchment. But the @CityofCT is not afraid of the water. 💧
• • •
Missing some Tweet in this thread? You can try to
force a refresh
Yesterday I walked from the N7 Highway to the Milnerton Lagoon Mouth to see for myself the challenges facing the Diep River. I was joined by @CityofCT officials. We met community members & user groups along the way.
Along this 15 kilometres stretch of river key challenges we saw were land invasion below the floodline, pollution from industrial run off, and sewage ingress from informal communities.
The community members we met along the river, and user groups such as the Milnerton Horse Riding School, all have a common desire to see a healthy and safe river.
1. Today Deputy Mayor @AndrewsEddie & I helped open the weir at Rondevlei Nature Reserve for the first time since 1998! After a brief boat ride we joined conservation staff in the water to open the sluice gate.
2. This draining of the waterbody simulates the natural draw-down that historically happened in this ecosystem. It will also flush excess nutrients from the waterbody & allow conservation staff to remove invasive Water Hyacinth (Eichhornia crassipes).
3. We also had a great 1st meeting The Friends of Zeekoevlei & Rondevlei who contribute an immense amount of capital & expertise to these waterbodies. They will be important roleplayers in the Water & Wetlands committee which I chair.
Today @CityofCT officials began clearing sludge & bullrushes at Rondevlei Nature Reserve in preparation of the vlei draw-down expected to happen later this week.
Here’s why this is important:
1. Rondevlei (250Ha) is a globally renowned birding site. On an average summer day 70 bird species may be seen. It also home to the #ExtinctintheWild Erica verticillata & Cape Town’s only Hippo pod! 🦛
Managing for biodiversity = Managing for ecotourism.
2. Hundreds of years ago #CapeFlats vleis would have dried up significantly during the dry summer months. The opening of the sluce gates will allow conservation staff to clear invasive aquatic Water Hyacinth (seen in the foreground).