WMS infoMapAccessService groundwater database Immo Blecher Water Research Commission pointOfContact +27 83 272 6791 immo@blecher.co.za conditions unknown None 3000 3000 text/xml image/jpeg image/png image/png; mode=16bit image/png; mode=8bit image/png; mode=1bit application/dxf text/plain text/html text/xml application/vnd.ogc.gml application/vnd.ogc.gml/3.1.1 application/json application/geo+json image/jpeg image/png application/json text/xml text/xml XML wrc_gw_db infoMapAccessService groundwater database CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 17.52497 20.279674 -34.509893 -32.616523 project_area The area identified to include in the "Cape Town and Environs" groundwater database project, which includes most of the Berg Water Management Area and the western part of the Breede Water Management Area. The area was specifically chosen to include the major dams supplying Cape Town with drinking water, but which are not within the Cape Town Metropolitan Municipality. water management areas department of water and sanitation department of water affairs CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 17.84384 20.01081 -34.42969 -32.700409 text/html grid CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 17.75 20.25 -34.5 -32.5 geosites Sites in the database CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 17.7983 19.923141 -34.432459 -32.718595 boreholes Includes a well, excavation, or any other artificially constructed or improved underground cavity which can be used for the purpose of intercepting, collecting or storing water in or removing water from an aquifer; observing and collecting data and information on water in an aquifer; or recharging an aquifer. [Source: National Water Act (Act No. 36 of 1998)]. A borehole is a constructed hole in the ground from which groundwater can be abstracted, recharged or observed. A wellpoint is similar to a borehole, but normally larger in diameter and often only a few metres deep. They are used for the extraction of shallow groundwater, sometimes located in rivers/streams extracting the shallow groundwater from the river bed. A wellpoint or drive point is a pipe with wall openings large enough to allow water to enter and small enough to keep water-bearing formation in place. A dug well is a shallow large diameter man-made pit or hole, from which groundwater can be abstracted. A dug well is mostly constructed in soft geological formations such as alluvium adjacent to rivers. The pit is normally dug by hand or using an excavator and generally has a diameter larger than 0.5 m. borehole groundwater wellpoint dug well CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 17.88808 19.86051 -34.38117 -32.75277 text/html springs Definition: A point where subsurface water emerges at surface, usually as a result of topographical, lithological or structural controls. Description: Springs are points or areas were groundwater exits the subsurface environment, either as a result of gravity or pressure. They can be perennial or ephemeral and can yield either small or large volumes of water. Famous springs in South Africa include Malones Eye and the Uitenhage Spring. spring fountain eye groundwater CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 18.05023 19.75897 -34.303083 -32.93274 text/html seepage_ponds Seepage ponds are typically small water reservoirs into which seepage for shallow sub-surface water infiltrates. These can be used for water extraction to dewater building basements , but they may also be ponds filled with water from mining or other industrial activities and are then used for evaporation. seepage monitoring observation CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 18.09756 19.69294 -34.07075 -32.957769 monitoring_stations Rivers/streams/canals are monitored for flow (discharge), stage height and water quality. Flow is the total volume of a fluid that flows past a fixed point in a river or stream over time. It is comparable to the speed at which a volume of fluid travels. There are numerous ways to measure flow rate, such as the bucket method, the float method, weirs and meters. Often only the surface water level (stage height) is recorded. Dam and pan levels are monitored by continously reading the surface water level height (negative) and, when overflowing, the height of water over the wall (positive), also called the stage height . river monitoring observation flow stage height CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 18.197577 19.70138 -34.40527 -33.02485 text/html meteorological_stations Meteorological or whether stations can record various parameters with often sophisticated and specialised equipment. These include rainfall, evaporation, wind speed and direction, humidity, temperature and others. rainfall evaporation monitoring observation CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 17.8558 19.9031 -34.353389 -32.8278 text/html monitoring_networks Groundwater, surface water and meteorology networks CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 17.798426 19.922241 -34.429157 -32.793138 wl_monitoring Groundwater level monitoring boreholes belonging to the HYDSTRA monitoring network of the Department of Water and Sanitation (DWS). Currently monitoring stations do not have "real-time" monitoring data available, but a longer term record can be viewed by clicking on the link, which will open the DWS NIWIS website where one can zoom to the relevant station manually. All the Department’s monitoring data is firstly uploaded and acts as DWS main database. This includes logger data, hand measurements and real-time monitoring data. From HYDSTRA groundwater data is then exported to the NGA and NIWIS or for any other user. The NGA, for example, receives only one measurement value for a geosite per day although all the 12 min. readings are available on HYDSTRA. monitoring groundwater borehole water level NIWIS HYDSTRA CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 17.96586 19.12374 -34.08374 -32.863329 text/html river_monitoring_stage_heights Rivers/streams are monitored for flow (discharge), stage height and water quality. Flow is the total volume of a fluid that flows past a fixed point in a river or stream over time. It is comparable to the speed at which a volume of fluid travels. There are numerous ways to measure flow rate, such as the bucket method, the float method, weirs and meters. Often only the surface water level (stage height) is recorded. Not all monitoring stations have "real-time" monitoring data available, but the ones that have will show a link to the "real-time" charts. river monitoring observation flow stage height CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 18.34548 19.70138 -34.40527 -33.06179 text/html dams_monitoring_stage_heights Dam and pan levels are monitored by continously reading the surface water level height (negative) and, when overflowing, the height of water over the wall (positive), also called the stage height. The capacity is expressed as a percentage of total volume that can be stored in the dam. Not all monitoring stations have "real-time" monitoring data available, but the ones that have will show a link to the "real-time" charts. dam pan monitoring observation stage height capacity flow CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 18.197577 19.58071 -34.21604 -33.02485 text/html monthly_rainfall Average monthly and annual total rainfall in [mm] rainfall evaporation monitoring observation CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 17.8558 19.9031 -34.353389 -32.8278 text/html gw_chemistry Various parameters characterised from borehole waters CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 17.829104 19.881703 -34.415454 -32.719334 ec Electrical conductivity is a measure of how well a material accommodates the transport of electric charge. The more salts dissolved in the water, the higher the EC value. It is used to estimate the amount of total dissolved salts, or the total amount of dissolved ions in the water. The SANS 241: 2015 limit for health risk concentration is 170 mS/m The SA Domestic Water Quality Guide specifies the following limits: Class 0: 0 - 70 Class 1: 70 - 150 Class 2: 150 - 370 Class 3: 370 - 520 Class 4: > 520 ec electrical conductivity water quality CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 17.88808 19.86051 -34.38117 -32.75277 text/html iron Although a low level of iron cannot do much harm, iron in water is considered as a contaminant because it also contains bacteria that feed off it. In addition to this, high iron content leads to an overload which can cause diabetes, hemochromatosis, stomach problems, nausea, and vomiting. The SANS 241: 2015 limit for health risk concentration is 2 mg/l The SA Domestic Water Quality Guide specifies the following limits: Class 0: 0 - 0.5 Class 1: 0.5 - 1 Class 2: 1 - 5 Class 3: 5 - 10 Class 4: > 10 iron water quality WHO CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 17.88808 19.86051 -34.38117 -32.75277 text/html borehole_properties Borehole (and well) properties like yield, aquifer type and depth CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 17.795294 19.92381 -34.440781 -32.718149 borehole_depth A borehole is a constructed hole in the ground from which groundwater can be abstracted, recharged or observed. Includes a well, excavation, or any other artificially constructed or improved underground cavity which can be used for the purpose of intercepting, collecting or storing water in or removing water from an aquifer; observing and collecting data and information on water in an aquifer; or recharging an aquifer. [Source: National Water Act (Act No. 36 of 1998)]. borehole groundwater CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 17.88808 19.86051 -34.37906 -32.75277 text/html borehole_yield Definition: The amount of water from a borehole, aquifer or water resource within a specified time. The volume of water per unit of time blown from the borehole during drilling. The blow yield is the rate at which water is blown from a borehole during drilling. A blow yield test is usually conducted once the borehole is completed to provide an indication of borehole yield. borehole groundwater CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 17.8558 19.9031 -34.40527 -32.75277 text/html administrative CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 15.838307 34.473397 -35.427135 -21.69047 roads Major roads excluding residential roads, tracks, cycleways and service roads roads highway arterial primary secondary tertiary CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 16.472803 32.858995 -34.832609 -22.127774 text/html wmas National Water Act Definition: A Water Management Area (WMA) is an area established as a management unit in the National Water Resource Strategy within which a Catchment Management Agency will conduct the protection, use, development, conservation, management and control of water resources in South Africa. [Source: National Water Act (Act No. 36 of 1998)]. water management area control of water resources national water act CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 16.469217 32.891854 -34.834214 -22.1245 text/html towns The major towns and cities of the Western Cape towns cities CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 17.920965 32.124814 -34.191632 -23.021781 municipalities Municipalities of South Africa, Metropolitan and Local. municipality metro metropolitan CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 16.451889 32.944981 -34.834171 -22.125029 text/html hydrology CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 15.215578 35.88058 -35.473102 -19.322192 dams_lakes Dams are man-made water storage reservoirs that can be used to store water or restrict river flow. Lakes are natural water storage areas filled with water, localized in a basin, that are surrounded by land, apart from any river or other outlet that serves to feed or drain the lake. dam lake man-made CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 18.33258 32.880969 -34.751947 -22.188031 text/html rivers Rivers are divided into perennial (always flowing), non-perennial (flowing occasionally, normally during the wet season), or dry rivers (only flowing seldomly during flash floods). The suffix normally describes the size, where a "River" would be quite a large volume flow, while a "Spruit" would be a small rivulet. rivers perennial non-perennial CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 15.983329 33.999253 -34.76999 -19.791433 catchments Catchment in relation to watercourse or watercourses or part of a watercourse, means the area from which any rainfall will drain into the watercourses or part of a watercourse through surface flow to a common point or points. [Source: National Water Act (Act No. 36 of 1998)] Synonyms: Drainage Basin, Watershed Description: The area from which water - which could include both surface and subsurface water - drains towards a common point. The surface and subsurface catchment areas may not coincide. The extent of catchment areas is defined by hydrological divides. This is a term essentially used by surface hydrologists. catchment river watershed drainage basin CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 16.453927 32.888318 -34.834 -22.123357 text/html hydrogeology Hydrogeological point and polygon layers like deopth to water level, lithology/geology, groundwater occurrence etc. CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 15.845258 34.418878 -35.427922 -21.692232 depth_to_wl The depth to the water level gives an indication of how deep a borehole/well would have to be to reach the top of the groundwater. From that level to the bottom of the hole (or the pump inlet) would then be the available drawdown. groundwater water level CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 17.88808 19.86051 -34.38117 -32.75277 faults In geology, a fault is a planar fracture or discontinuity in a volume of rock across which there has been significant displacement as a result of rock-mass movement. Faults are preferred pathways for groundwater movement and, depending on width, weathering, composition and other factors, are detectable and traceable with geophysical equipment for siting boreholes. geology fault tectonics CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 16.545154 32.279309 -34.716378 -22.138576 lithology The lithology of a rock unit is a description of its physical characteristics visible at outcrop, in hand or core samples, or with low magnification microscopy. Physical characteristics include colour, texture, grain size, and composition. See also https://en.wikipedia.org/wiki/Lithology in Wikipedia for more explanations. chronostratigraphy lithology geology borehole log CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 16.458894 32.8918 -34.832352 -22.12268 application/pdf gw_occurrence Groundwater occurs in aquifers. Aquifers are geological formations which hava structures or textures that hold water or permit appreciable water movement through them. [Source: National Water Act (Act No. 36 of 1998)]. A formation, group of formations, or part of a formation that contains sufficient saturated permeable material to store and transmit water; and to yield economical quantities of water to boreholes or springs. A fractured aquifer is defined as a formation that contains sufficient fissures, fractures, cracks, joints and faults that yields economic quantities of water to boreholes and springs. Intergranular aquifers are aquifers in which groundwater flows in openings and void space between grains or weathered rock. aquifer groundwater fractured intergranular CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 16.458894 32.891663 -34.832352 -22.12268 text/html harvest_potential The Groundwater Harvest Potential Map was the first attempt to provide quantitative information on sustainable rates of groundwater abstraction in South Africa on a country-wide basis. Harvest Potential gives the maximum rate at which groundwater can be sustainably abstracted. Local socio-economic or environmental factors could reduce this considerably. This map is intended to provide a national overview and perspective on sustainable abstraction. It cannot be used for local planning, development or management of groundwater. Such exercises require local investigations and assessments. groundwater harvest potential CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 16.458047 32.895797 -34.839726 -22.126401 text/html borehole_prospects Borehole prospects is a measure of the ease or difficulty with which groundwater will be struck during drilling of a borehole. This is a statistical analysis of historical boreholes drilled in an area. A successful borehole is a borehole with a yield of at least 0.1l/s, while a borehole with > 2l/s is regarded as a "strong" borehole. borehole prospects drilling groundwater CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 16.458021 32.895974 -34.839829 -22.126611 more_basemaps Additional basemaps from local WMS servers CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 15.309616 34.574619 -35.599824 -21.563974 imagery_50cm The latest 50cm resolution imagery of the Chief Directorate: National Geo-spatial Information. CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 16.448201 32.901803 -34.8518 -22.098201 topo_250k The latest 1:250000 scale topographic maps of the Chief Directorate: National Geo-spatial Information. CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 16 33.000156 -35.000075 -22 topo_50k The latest 1:50000 scale topographic maps of the Chief Directorate: National Geo-spatial Information. CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 16.25 32.999972 -34.849985 -22 Overview CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 15.838329 34.473397 -35.427135 -21.690988 project_area_overview The area identified to include in the "Cape Town and Environs" groundwater database project, which includes most of the Berg Water Management Area and the western part of the Breede Water Management Area. The area was specifically chosen to include the major dams supplying Cape Town with drinking water, but which are not within the Cape Town Metropolitan Municipality. water management areas department of water and sanitation department of water affairs CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 17.84384 20.01081 -34.42969 -32.700409 text/html provinces CRS:84 EPSG:4326 EPSG:32734 EPSG:3857 16.451909 32.94498 -34.834171 -22.12503