This chapter presents to support a preliminary assessment of the waterbody situation, gives an overview of measures that may be taken within a waterbody to control cyanobacterial growth and bloom formation, and also gives guidance on the questions to address when considering the implementation of internal measures. While site inspection is highly valuable for assessing the risk of cyanobacterial proliferation or blooms, taken alone this may not be sufficient to assess this risk because of the inherent variability of cyanobacterial occurrence. River management strategies to generate higher flow and reduce the risk of cyanobacterial blooms depend upon the availability, cost and ability to deliver enough water to provide that flow. Whether climate change will enhance cyanobacterial proliferation in a specific waterbody depends on which way the impacts of warming and the associated changes in the aquatic ecosystem will interact – resulting in a potential increase or decrease in the dominance and biomass of cyanobacteria.