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OH megamasers (OHMs) are rare, luminous masers found in gas-rich major galaxymergers. In untargeted neutral hydrogen ($\mathrm{HI}$) emission-line surveys,spectroscopic redshifts are necessary to differentiate the$\lambda_\text{rest}=18$ cm masing lines produced by OHMs from $\mathrm{HI}$ 21cm lines. Next generation $\mathrm{HI}$ surveys will detect an unprecedentednumber of galaxies, most of which will not have spectroscopic redshifts. Wepresent predictions for the numbers of OHMs that will be detected and thepotential "contamination" they will impose on $\mathrm{HI}$ surveys. We examineLooking at the Distant Universe with the MeerKAT Array (LADUMA), asingle-pointing deep-field survey reaching redshift $z_\mathrm{HI}=1.45$, aswell as potential future surveys with the Square Kilometre Array (SKA) thatwould observe large portions of the sky out to redshift $z_\mathrm{HI}=1.37$.We predict that LADUMA will potentially double the number of known OHMs,creating an expected contamination of 1.0% of the survey's $\mathrm{HI}$sample. Future SKA $\mathrm{HI}$ surveys are expected to see up to 7.2% OHcontamination. To mitigate this contamination, we present methods todistinguish $\mathrm{HI}$ and OHM host populations without spectroscopicredshifts using near- to mid-IR photometry and a k-Nearest Neighbors algorithm.Using our methods, nearly 99% of OHMs out to redshift $z_\mathrm{OH} \sim 1.0$can be correctly identified. At redshifts out to $z_\mathrm{OH}\sim2.0$, 97% ofOHMs can be identified. The discovery of these high-redshift OHMs will bevaluable for understanding the connection between extreme star formation andgalaxy evolution.

OH Megamasers in HI Surveys: Forecasts and a Machine Learning Approach to Separating Disks from Mergers