OUAT

Framework for Hydrology

Water received as rainfall in a watershed gets converted into 4 fractions namely, Evapotranspiration, Soil Moisture, Run Off and Groundwater. Methods and models for estimating these fractions starting at the LMU/ micro watershed scale and going up to watershed scale are needed for preparing the Water Balance in a given area
REWARD would encourage the use of existing methods and models or where required existing models could be adapted, calibrated and validated for use at the indicated scales. New models may be developed and used after suitable validation only where no models exist or are not suitable for use at the scale required or are not at the desired resolution.
Models adapted or developed must be easy to use, extendable to use in new areas with minimal requirement of calibration.
Using outputs from these models, tools for estimating water balance from LMU to watershed scale needs to be prepared.

In conjunction with land resources data, models/tools for deciding location of water harvesting and conservation structures and the volume of water expected at those sites are to be developed.
These models must consider existing structures, their actual storage, overflow, expected, run off from independent catchments for proposed structures, etc.
In designing siting and volume of these structures, upstream and downstream externalities up to watershed scale should be accounted for and built into the model.

Based on hydrogeological studies, models/tools for different LMUs are to be developed for siting ground water recharge and extraction structures. Parameters such as infiltration, permeability, hydraulic conductivity, water holding capacity, field capacity, PWP etc., need to be characterised for different LMUs and used in the model.
Methods/models to be identified for estimating the amount of recharge at the micro watershed/SWS levels; and if need be to recalibrate/refine/develop new ones.
A simple community/farmer level groundwater tool needs to be developed to estimate recharge based on rainfall received and quantum of extraction that is sustainable at the micro/sub watershed level.

Develop rapid assessment tools to characterise watersheds into surplus, adequate and deficit categories based on water balance. The tools should characterise at the micro watershed level but take into account hydrologic issues at least upto the watershed scale.
Micro/sub watersheds characterised as Surplus and Adequate would benefit from both supply and demand side interventions, while Deficit ones would need only demand side interventions.

Develop a model for assessing water needs of various sectors such as crops, livestock, drinking water, etc., at micro watershed scale and match with water balance.
The model should allow communities to allocate water to various sectors based on rainfall-linked water balance that is assessed every season.

Develop a model for use by communities for selection of crops/varieties based on growing period and water budget. This model is expected to apply a water lens to crop suitability classification that is based on LRI data.
Once crops/varieties are selected, models to assess/predict crop response to water (rainfall + irrigation) in different agro-climatic conditions and LMUs are needed to find ways to increase Water Productivity and Water Use Efficiency in watersheds.
Based on these models provide advisories to farmers on crop selection and water management to maximise water productivity.
6. Develop protocols/guidelines needed for participatory ground water management at village/watershed level.