5th lesson sustainable use of water by Cuscostudio

01PQKPQ Cusco Sun City: an experimental territory on the site of the Alejandro Velasco Astete Airport

materials science

Laboratorio materiali

5th lesson_sustainable use of water Simonetta Pagliolico Politecnico di Torino

water supply and withdrawals Global water withdrawal by sector

SOURCE: Igor A. Shiklomanov, State Hydrological Institute, St. Petersburg, Russia, and UNESCO, Paris (1999).

water cycle

domestic water use and demands

Stormwater Management

Beat Stauffer, seecon international gmbh http://www.ssswm.info/ http://creativecommons.org/licenses/by/3.0

Copyright & Disclaimer •Copyright •Included in the SSWM Toolbox are materials from various organisations and sources. Those materials are open source. Following the open-source concept for capacity building and non-profit use, copying and adapting is allowed provided proper acknowledgement of the source is made (see below). The publication of these materials in the SSWM Toolbox does not alter any existing copyrights. Material published in the SSWM Toolbox for the first time follows the same open-source concept, with all rights remaining with the original authors or producing organisations. •To view an official copy of the the Creative Commons Attribution Works 3.0 Unported License we build upon, visit http://creativecommons.org/licenses/by/3.0. This agreement officially states that: •You are free to: – Share - to copy, distribute and transmit this document – Remix - to adapt this document. We would appreciate receiving a copy of any changes that you have made to improve this document. •Under the following conditions: – Attribution: You must always give the original authors or publishing agencies credit for the document or picture you are using.

•Disclaimer •The contents of the SSWM Toolbox reflect the opinions of the respective authors and not necessarily the official opinion of the funding or supporting partner organisations. •Depending on the initial situations and respective local circumstances, there is no guarantee that single measures described in the toolbox will make the local water and sanitation system more sustainable. The main aim of the SSWM Toolbox is to be a reference tool to provide ideas for improving the local water and sanitation situation in a sustainable manner. Results depend largely on the respective situation and the implementation and combination of the measures described. An in-depth analysis of respective advantages and disadvantages and the suitability of the measure is necessary in every single case. We do not assume any responsibility for and make no warranty with respect to the results that may be obtained from the use of the information provided. •

1. Concept

What is Stormwater Management? Why: • Surface runoff has to be reduced to prevent flooding • Especially in urbanised areas where natural infiltration is reduced • Sediments and Pollutants (e.g. nutrients from agriculture) must be removed How: • Temporary storage (e.g. retention ponds, rainwater harvesting) • Infiltration (e.g. grass filter stripes, infiltration basin)

1. Concept

Rural Stormwater Management Causes: heavy rainfalls, storms, roads, buildings, overstrained sewer systems Impacts: flooding and stream erosion Benefit of flood events and precipitation: use this water for irrigation Some available techniques:  Spate irrigation  Micro basins  Sand Dams  Field trenches  Rainwater harvesting Flooded agricultural land after a storm event. Source: ARC (2010)

1. Concept

Rural Stormwater Harvesting

Rooftop harvesting and storage for further use. Source: DOLMAN & LUNDQUIST (2008) Spate irrigation system Yemen. Source: FAO (2012) Sand accumulates until the dam is completely full of sand up to the spillway. Water is stored within the sand, protected and filtered, making up to 40 % of the total volume. Source: ED (n.y.)

1. Concept

Urban Stormwater Management

(CSIR 2000; PARKINSON et al. 2010)

Human settlements disturb the natural water cycle and creates floods and water pollution:  Natural vegetation is often removed and rivers are canalised  Surfaces are impermeable  Groundwater resources decrease, fresh water becomes scarce

Let’s upgrade the urban water cycle! 11

Source: AUCKLAND CITY COUNCIL (2010)

1. Concept

Urban Stormwater Management – IUWM Approach (UNEP 2009)

Integrated Urban Water Management (IUWM): The practice of managing freshwater, wastewater, and stormwater as links within the resource management structure, using an urban area as the unit of management.

Including: • Consumption efficiency • Ensure water quality • Alternative sources (e.g. rainwater) • Engage communities • Establish and implement policies and strategies • Support capacity development of personnel and institutions • Improve economic efficiency of services 12

2. How it can optimise SSWM â&#x20AC;˘Stormwater Management helps to collect, treat and (re-)use runoff water; to avoid contamination and destruction; and to restore the disturbed urban water cycle!

Source: SEECON (2010)

3. Design Principles

Urban Stormwater Management – An Overview There are several techniques to manage surface runoff. They are divided in two groups:

 Storage Type Devices  Infiltration Type Devices What technique is implemented should be decided on local conditions and responsible planers. The sewer system cannot handle the volume of runoff. Source: USGS (2009)