By Ecovillage Cluster 1B resident, Alex Jolly
With increasing housing occupation, spring rains finishing early, and hot spells well underway, it’s a great opportunity to provide fellow Ecovillagers with a high-level overview of how our water system balancing is working against budgets.
We have a weather station located in Cluster 1B, which has been continuously logging data to the web since September 2022, and is providing us with rainfall information, temperature, pressure, humidity, wind speed / direction, UV index and Watts per square meter. The data is freely available to anyone interested in looking at current or historical data logged by our weather station “IWITCH1” on the Weather Underground website: https://www.wunderground.com/dashboard/pws/IWITCH1
For the record we received 928mm (Nov 21 – Oct 22) and 959mm (Nov 22 – Oct 23) albeit it’s been a little erratic this year, with above average falls in April and June, while other months have mostly been below average. The historical BOM annual rainfall average for Witchcliffe is 1004mm.
Dam water consumption and balancing is starting to provide some interesting information, now that all civil construction has been completed, the wastewater treatment plant (WWTP) is up and running, and a number of clusters that are now well established in terms of residents and garden areas.
The northern “Stingray” dam (approx 100ML) and the southern dam (approx 100ML) are connected, and both provide water for our community gardens, Exclusive Use Areas (vegie patches), Agricultural lots, firefighting tanks, playing oval and vineyard. Daytime solar pumps replenish our tanks from the southern dam, while night pumping where required, will draw from Stingray dam using grid power during off peak charge periods. While the central dam (50ML) is connected to southern dam, its primary purpose is for wildlife and conservation, and as a backup water supply as needed for emergencies or serious drought conditions.
Wastewater treatment plant
The WWTP is functioning well, generating 12kL daily (at the current Ecovillage occupancy) for watering the avocados. However, the avocado orchard requires 24kL per day for around 225 days a year. Therefore, the wastewater treatment plant dam, located adjacent to the WWTP, which has been topped up from rainwater over the past couple of years, will be used to supplement the shortfall of treated water. The avocado orchard will be completely self-sufficient from the daily treated wastewater once we have 120 homes occupied.
Water tank readings from the clusters (community gardens and EUAs) are showing good signs of remaining at or below the annual water budget of 3mL (3,000kL). The results for stages 1 to 3 are tabled below in kL for the period Nov 2022 to Oct 2023. Stage 1 clusters are reasonably well established with each cluster below budgeted water. It is envisaged community garden trees and shrubs will require less water as they become well established, which should result in better water consumption results than tabled below.
Water tanks for community gardens and EUA’s in stages 4 and 5 have been charged with dam water this month, and will be included in water balance reporting from Dec 2023.
With early sunrises providing solar power and less wind in the early mornings, our clusters should ideally consider optimal early morning lawn watering times to conserve water and use household generated solar power for their cluster irrigation pumps where possible.