Does NASA police urine production by astronauts?

Question

Acute abdominal pain is a medical emergency which requires diagnostic facilities not available on board spacecraft. It could require emergency return from LEO or mission abort in cislunar missions. One of the causes of acute abdominal pain is renal stones.

https://pubmed.ncbi.nlm.nih.gov/26456109

Bone loss and renal stone risk are longstanding concerns for astronauts. Bone resorption brought on by spaceflight elevates urinary calcium and the risk of renal stone formation... Regardless of exercise, the risk of renal stone formation increases during spaceflight. A key factor in this increase was urine volume, which was lower during flight in all groups at all time points. Thus, the easiest way to mitigate renal stone risk is to increase fluid consumption.

Prolonged microgravity causes significant calcium loss in bones (10 times the rate seen in Earth-bound osteoporosis), thereby increasing the risk of kidney stones. https://www.nasa.gov/mission_pages/station/research/benefits/bone_loss.html

Between 1% and 15% of people globally are affected by kidney stones at some point. In 2015, they caused about 16,000 deaths worldwide… By far, the most common type of kidney stones worldwide contain calcium. https://en.wikipedia.org/wiki/Calcium_oxalate#Kidney_stones

Acute abdominal pain in an ISS crewmember would necessitate return to Earth, along with the other crew in that Soyuz/Crew Dragon crew group. The same event on a Lunar mission would cause a mission abort. On a Mars mission...?

Since the risk of kidney stones can be reduced by maintaining adequate urine volume, "which was lower during flight in all groups at all time points", does NASA routinely “police” astronaut urine production (monitor urine production and enforce fluid consumption)?

Answer 1

For shuttle:

• There was no enforcement of and no policy existed regarding urine production per crewmember.
• Even if such a policy had been desirable, there was no way to monitor per-crewmember urine production.

The shuttle toilet (formally, "Waste Collection System (WCS)") had no telemetry associated with it. (See this answer for a WCS overview) The responsible flight control group EECOM had to infer when toilet ops were ongoing by monitoring other signatures in the orbiter systems:

• AC current signatures from operation of the WCS fans
• Change in pressure over time (dp/dt) of the cabin atmosphere for a toilet flush
• Quantity changes in the waste water tank

Source: Shuttle ECLSS Training Manual (annotations mine)

This answer does not apply to dedicated life science experiments such as those conducted during the Spacelab Life Sciences missions which may have monitored per-crewmember urine production using a Urine Monitoring System.