Whatshot
April Floods Linked To "Deluge" Conditions In May - A Wake-up Call
April Floods Linked To "Deluge" Conditions In May - A Wake-up Call
Date: 2022-05-26
"CLIMATE CHANGE" is now a REALITY with loss of our natural Land Resources, collapse of Roads and Bridges, Loss of Property regardless of size, dimension or usage, and last but not least Loss of Life. Heavy Rainfall during the Flood period from 11th April has wiped out all previous charts in Durban, with a new Record of 300 mm to 350 mm over a 24 hour period. This Record lays down the basis for all new Pre and Post Construction calculations, which should be submitted at the Planning Stage, by the nominated Engineer and his construction Team.
The aeolian wind-blown sands have formed steeply sloping Dunes throughout the ages. Where there is bare land with exposed soil, often with old sugar cane roots removed, grasslands sprayed and removal of rooted species near to river banks and within slopes, the displacement of topsoil is inevitable during heavy rainfall. Sub-surface layers are exposed with often Berea Red Clay providing the ingredient for a mass of mobile mud which, as described by the well-know ecologist, the late Roddy Ward, "the COLLOIDAL MASS increases the Volume of Flow and may double the weight impact". The Umdhloti area with many east facing residential homes and gardens along Bellamont Road has suffered extensive, and costly damage from the "Colloidal" build-up with invasive mud-flows from the upper catchment. Enormous erosion fissures now cleave through the steep Dune slopes, and Protected "D'MOSS" Forest areas.
The uncontrolled precipitation runoff and increasing colloidal mass mobility have caused collapse of building apartments, loss of septic tanks, blockage of internal stairways, lifts and parking areas. The downward path of destruction has invaded many Apartment Buildings, before blocking the Promenade like an earthquake. Here all traffic has been brought to a standstill, highlighting that in times of crisis or Emergency there is NO ESCAPE; not possible for Police, Fire or Ambulance to make entry and assist.
Laid down Procedures must be in place, applied and achieve EXCELLENCE OF STORMW ATER MANAGEMENT and COMPLIANCE for the entire period of Construction with 'CONTINUlTY' for the "Occupational" Phase thereafter. The Procedures to be Site Specific" with methodology, to enable Stormwater Capture, avoid and reduce Run-off, and ensure compliance with Estate Management criteria, Local Regulations, the Water Act with provision of Licenses, together with Health & Safety Regulations.
The time is here for all Architects to engage a new structural approach to CAPTURE THE RAIN WATER "AT SOURCE". This premise is nothing new and was identified in Zimbali in 1996 by the Professional Team. The expanse and type of roof structure indicates the surface RUN-OFF calculation, the size of gutter must capture the VOLUME OF FLOW, with down pipes and collection drains and storage tanks to complete the design criteria. This is not rocket science! Compromise of the Sewer Systems, Stormwater and drainage infrastructure at the Planning stage invites Nature's revenge on mankind's neglect.
Similarly, a "Site Specific Assessment" by a Landscape "Specialist" must comprehensively cover the topography, the soils, any water Resource or "Wetland", the Indigenous Environment and present an integrated approach with the Built Environment. Then the "Specialist's" Rehabilitation Design, should include the methodology advised and hnplemented for all Banks and Slopes for the Angle of Repose to the toe of the slope and must entertain the "Category of Risk". The Natural Environment dictates the selection of indigenous trees, shrubs, fems, succulents, grass and groundcovers to RESTORE THE WORLD OF THE MAKER. For the Umdhloti Area sincere thanks and appreciation are conveyed to The Sea Rescue Team.

