hydration in the local climate: how much and what to drink

Los Angeles adults who run or hike regularly should aim for 3.2 liters of total fluid intake on days when temperatures reach 82 degrees or higher, according to guidelines from the county health department released in early 2026.

The dry air and low humidity that settle over the basin each July increase water loss through skin and breath, even for people who spend only an hour on the Strand or in Griffith Park. Beach runs from Santa Monica to Malibu and weekday hikes on the trails above the observatory have become year-round habits, yet many participants still track their intake by coffee cups rather than actual volume. The result shows up in emergency room visits that climb each summer when residents arrive dehydrated after morning workouts.

Where locals fill their bottles

At the Santa Monica farmers market on Arizona Avenue, vendors sell electrolyte packets that runners mix into stainless bottles before heading south along the bike path. A block inland on Main Street, the store called The Juice serves coconut water blended with sea salt for $5.75; staff say sales double on days the marine layer burns off by 10 a.m. Griffith Park visitors can refill at the public fountains near the Merry-Go-Round, though the Los Angeles Department of Recreation and Parks advises adding electrolyte tablets when hikes exceed 90 minutes.

A 2025 UCLA Fielding School analysis of 1,200 local adults found that people who drank only plain water during outdoor activity replaced just 62 percent of fluid lost in sweat, while those who alternated with beverages containing sodium and potassium reached 91 percent replacement. The same report noted that reusable bottles purchased at local running shops average $28 and last two seasons before the insulation degrades.

Putting the numbers into practice

Start the day with 500 milliliters of water before leaving home. During a 45-minute run along the coast, carry 750 milliliters mixed with one electrolyte packet. After returning, replace the remainder with a meal that includes fruit or a small green smoothie. On non-exercise days, plain tap water from the LADWP supply meets most needs when paired with typical meals. Residents who feel lightheaded or notice darker urine should add an extra 250 milliliters mid-afternoon rather than waiting until evening. Those with medical conditions should check personal targets with a physician before changing routines.