Digital twins (DTs) are increasingly proposed for wastewater bioprocesses to boost resilience, cut emissions and accelerate circular resource recovery, yet many projects stall when modelling ambition outpaces process, data fitness and on-site controllability. We introduce a three-dimensional TRL–DRL–α assessment that scopes credible twin roles and de-risks deployment by jointly evaluating technology readiness (TRL), data readiness (DRL) and an alignment factor (α) describing alignment between the process, available data streams and intended twin model. TRL defines the feasible operating envelope; DRL captures data quality, availability and task fitness; α scores cross-layer alignment across technology-to-data (sensing and sampling resolve key dynamics), data-to-model (variables, synchronisation and coverage support inference) and model-to-technology (outputs match decision hierarchy and actionable levers). Each dimension is rated on a five-point scale to expose key bottlenecks. The workflow produces a simple profile that shows which DT roles are realistically feasible at a given site, including testing “what-if” changes, tracking hidden process states in real time, and actively recommending or automating adjustments. It helps avoid over-promising, lowers deployment risk, and lists the key upgrades needed to reach the next capability level. In doing so, it shifts wastewater DTs from prototypes to deployable systems delivering operational and sustainability benefits.