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Brad Lancaster’s books on Rainwater Harvesting would have to be among the most consistently inspiring books we own. Two volumes into his trilogy on Rainwater Harvesting for Drylands and Beyond, Lancaster combines accumulated community wisdom with permaculture principles to produce lavishly illustrated, practical and highly accessible manuals for managing water in urban and rural environments. Consistent with permaculture thinking, Lancaster urges land managers to spend time observing the season patterns of the landscape to more effectively design for sustainable, integrated water management. One method of doing this is to compile a One Page Place Assessment, drawing together essential climatic and ecological information about your particular location.

Our first year has been one of spreadsheets, mapping out our seasonal observations and activities, and the One Page Place Assessment concept is a elegant way of compiling climatic data from Second Valley and the surrounding area. We’ve finally completed the first version of a place assessment for our property, with much of the data drawn from Bureau of Meteorology stations nearby (Myponga Reservoir being the furthest). While we have tailored information to our particular location, we hope it will be of use to other landowners in the region. We have also referenced information sources so others can draw on the same resources in exploring their own area.

You can download our One Page Place Assessment here.

Brad Lancaster has prepared a comprehensive rundown of each section of the One Place Page Assessment on his website, together with a detailed (North American-focussed) how-to. The first section on temperature averages, highs and lows, is self-explanatory and all data is drawn from the Bureau of Meteorology’s (BOM) online climate records. The second section on sun patterns is intended to support passive solar design in both buildings and plantings on the property. The shadow ratios for winter and summer solstices allow planning for the shadows cast by both trees and buildings, while calculating azimuths and sunrise and sunset positions allows for designing plantings and buildings to maximise or avoid solar exposure at particular points of the year.

An azimuth is the angle along the horizon from a reference direction (eg. south in the diagram) to a point of interest (the position of the sun). Diagram from http://www.harvestingrainwater.com/sun-shade-harvesting/winter-solstice-shadow-ratio-azimuth-table/

Azimuth angles combined with shadow ratios allow for the calculation of shadows and sun angles at certain times of the year. For example, you may want shade from a certain tree in summer, but to avoid it in winter to allow warmth into the house. Note the diagram is from the northern hemisphere and so oriented south. Diagram from http://www.harvestingrainwater.com/sun-shade-harvesting/winter-solstice-shadow-ratio-azimuth-table/

Wind data was gathered from the BOM and mostly seemed to match our own experiences. The NW-SE wind directions highlight the microclimate of the Fleurieu Peninsula. Average rainfall data is drawn from the BOM, and matched with evaporation data from both BOM mapping and State Department of Water, Land and Biodiversity Conservation reports. The BOM offers more detailed evaporation data at a fee. It’s worth noting that the evaporation rate is more than double the rainfall for the region, classifying it as a dryland environment.

The Totem Species refer to plants and animals historically or currently present in the region that may also be listed as vulnerable. We’ve interpreted these as species to target in designing habitat. We have chosen species that are currently present in the region, and have tried to identify species that are representative of the habitat type we wish to cultivate. The vulnerable Yellow-tailed Black Cockatoo is iconic on the Fleurieu, and while we’ve spotted it flying overhead, there’s currently nothing of interest on our block for them to be tempted to hang around. We’ve photographed the Painted Button-Quail, also listed as vulnerable, in perhaps the most hostile environment on our block, the arid bed of an erosion gully. Supporting its continued presence through habitat development is desirable. Currently considered in decline, the Scarlet Robin is an ideal woodland species, hunting for insects from the low branches of spreading woodland trees. We’re using the Scarlet Robin as a way of thinking about woodland habitat structure and a reminder of the need for low, spreading trees and open patches, habitat that will also hopefully allow other more common locals such as the Red-browed Finch to expand their territory. The Southern Brown Bandicoot is a nationally endangered species, however it has been recorded relatively close-by in and around the Myponga region, Second Valley forest and Deep Creek. In contrast, the Short-beaked Echidna is relatively common. We have sighted one nearby on a forested bend in the Congeratinga River, so there is a chance that the right habitat could support its expansion. While often seen in urban areas the Common Brushtail Possum is becoming increasingly uncommon in non-urban environments. Adelaide and Mount Lofty Ranges Natural Resources has a series of factsheets on state endangered and vulnerable species that provides a good overview of their habitat requirements and distribution.

Like everything else about this property, this Place Assessment is a work-in-progress. As we continue to dip into groundwater reports and soil mapping as part of our bedtime reading, we’ll to update the Assessment with more data as we find it. We welcome your ideas and suggestions too!

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