Madrona Marsh almost Wintertime
"A vernal marsh is a temporary pool of water that provides habitat for distinctive plants and animals. With no built-in water source, but located at the lowest point of the area, a vernal marsh is created by water collection from the runoff of the surrounding upland slopes. Vernal means spring, and typically the marsh is fed by winter and spring storms.
The depression which contains the Madrona Marsh is apparently a swale in the ancient dune sand caused by aeolian processes. The marsh is fed by drainage waters and by rainfall. It has no outlet. Before the development of the City of Torrance, water for the marsh was supplied through natural channels; now, there are several storm drains that flow into the marsh from the west side. Runoff from irrigation in the neighboring housing tracts flows into the marsh through these drains. During a rainstorm, there is heavy runoff into the marsh by these routes. Additionally, on the southeast corner of the Preserve, there is a sump that collects rainwater and runoff. Water from the sump is filtered and pumped up to the marsh in the wet season only. After the rainy season passes, evaporation, percolation, and transpiration reduce the water depth by about a quarter inch per day. In most years, by the end of August or early September, the Preserve is dry and remains dry until the next rainy season. The soils of the Preserve consist of fine sand silt and clay."
friendsofmadronamarsh.com
"Madrona Marsh is a 10-acre vernal preserve located in Torrance, California. ... The Madrona Marsh preserve is a remnant of the once extensive natural systems that existed along the coastal plain and terraces of Southern California. The marsh is situated on a piece of land that was set aside for oil production in 1924."
ushistory.com
Madrona Marsh almost Wintertime
"A vernal marsh is a temporary pool of water that provides habitat for distinctive plants and animals. With no built-in water source, but located at the lowest point of the area, a vernal marsh is created by water collection from the runoff of the surrounding upland slopes. Vernal means spring, and typically the marsh is fed by winter and spring storms.
The depression which contains the Madrona Marsh is apparently a swale in the ancient dune sand caused by aeolian processes. The marsh is fed by drainage waters and by rainfall. It has no outlet. Before the development of the City of Torrance, water for the marsh was supplied through natural channels; now, there are several storm drains that flow into the marsh from the west side. Runoff from irrigation in the neighboring housing tracts flows into the marsh through these drains. During a rainstorm, there is heavy runoff into the marsh by these routes. Additionally, on the southeast corner of the Preserve, there is a sump that collects rainwater and runoff. Water from the sump is filtered and pumped up to the marsh in the wet season only. After the rainy season passes, evaporation, percolation, and transpiration reduce the water depth by about a quarter inch per day. In most years, by the end of August or early September, the Preserve is dry and remains dry until the next rainy season. The soils of the Preserve consist of fine sand silt and clay."
friendsofmadronamarsh.com
"Madrona Marsh is a 10-acre vernal preserve located in Torrance, California. ... The Madrona Marsh preserve is a remnant of the once extensive natural systems that existed along the coastal plain and terraces of Southern California. The marsh is situated on a piece of land that was set aside for oil production in 1924."
ushistory.com