Weather Alert: Impact-based warning: Rain which could lead to localised flooding- Western Cape Province

In light of this severe weather alert as produced by the South African Weather Service (SAWS) and other centers, the following advisory guidelines are suggested. It is emphasized that these advisories are broad guidelines and should be interpreted considering the local aspects of the region such as soil types, cultural preferences and farming systems. Depending on the particular region, the prioritization of the guidelines will differ. The basic strategy to follow would be to minimize and diversify risk. The province should further simplify, downscale and package the information according to their language preference and if possible use local radio stations and farmers’ days in disseminating the information.

Impact-based warning issued by SAWS valid: 15 March 2021

Yellow (level 1) warning for rain could lead to localized flooding of roads and settlements over the coastal areas of the Overberg and Garden Route Districts in the Western Cape.

Heavy rainfall raises the water level. When the water level is higher than the river banks or the dams, water flows out from the river and flooding occurs.

Preventive measures:

• Construction of proper drainage systems – Drains must be cleaned constantly as they ensure proper water irrigation.
• Mechanical land treatment of slopes such as contour ploughing or terracing to reduce the runoff coefficient.
• Construction of small water and sediment holding areas.
• Construction of floodways (man-made channels to divert floodwater).
• Terracing hillsides to slow flow downhill.

What to do when flooding is forecasted:

Avoid-

• Cutting grass in the rainy season (nutrient depletion).
• Applying fungicides and pesticide (plants and animals).
• Applying N fertilizer (burning of plants) (Nitrogen loss is higher during heavy rain), immediately follows a surface application of fertilizer, especially on sloped areas.
• Dumping fertilizer in one spot can cause the roots below the fertilizer to be burned and die.
• Irrigation (waterlogging can occur, nutrient depletion).

–  Cover Urea licks to prevent them from becoming toxic.

–  Provide shelter for animals (young ones die easily).

–  Leave cultivated areas coarse.

–  Relocate/ move animals to a safe place.

The following are a number of concerns and recommendations:

• Be extra cautious for pest and diseases after the rain has fallen, as high moisture content and high temperatures may trigger these.
• Assume that floodwater contains sewage and might be harmful for human and livestock consumption.
• Before leading livestock across a river, check whether the water level is rising. This is especially necessary if it is already raining, but remembers that there could be a storm further upstream and floodwaters could be on the way

A comprehensive list of strategies can be found in the monthly NAC Advisory. It can be accessed from the following websites: www.dalrrd.gov.za. For more information contact:-

Directorate: Climate Change and Disaster Risk Reduction

Private Bag X93

Pretoria 0001

Tel: 012 319 6775

Email: MittaA@Dalrrd.gov.za

Weather Warning information as received from the Department of Agriculture, Land Reform and Rural Development.