3 Essential Water Filters for River Trips (and Other Clean Water Supply Tips)

MSR Gravity Water Filter on River

Keeping water-borne illnesses at bay on a river trip involves various sorts of water filters—in addition to bringing reliably clean drinking water with you. Each type of water filter has a different purpose while you’re floating or in camp, and during a multi-day river trip, you might need (or wish you had) any or all of them. Here’s a rundown of the different types of water filters for purifying river water and tips for using them, a guide to water purification chemicals to address viruses, and guidelines for carrying clean water with you. (Note: Some of these are affiliate links.)

Gravity water filters are perfect for river camp as they do their work while you’re doing other things

Best water filters for river trips

The three types of water treatments that will cover most river tripping situations are:

  1. Gravity filter systems
  2. Water bottles with filters
  3. Compact straw filters 
  4. Water purification chemicals

You won’t bring every type of filter on every trip, but it’s good to have an arsenal of filters in your gear to choose from. A case of giardia can ruin a boater’s trip. All the filters discussed here are commonly used for backpacking and camping situations and remove bacteria and protozoa, which are the common concerns if you’re boating in the U.S. or Canada.

Note that most water filters will not work on viruses such as norovirus, hepatitis A, or rotovirus—although that situation is rapidly changing as manufacturers such as Grayl and Epic Water Systems have introduced products with filters that work on viruses. If you’re concerned about viruses (norovirus has plagued river runners on some rivers in the past decade), combine filtering with a purifying chemical (more on that below). The Centers for Disease Control (CDC) has a handy chart for determining which water treatment methods work for which contaminants. Also keep in mind that you can remove all contaminants, including viruses, by boiling water for 1 minute, or 3 minutes if you’re above 6,500 elevation. Not practical for river running, but something to remember if you find yourself in camp with no clean water, no water filter, and plenty of campstove fuel.

Before we dive into the best use cases for each type of filter, let’s talk about the most obvious solution for ensuring clean water on a river trip—bringing it with you. 

Two humble water jugs that do the trick—one with a convenient spout (keep track of the red cap on the spout) and a jug from a military supply store

Tips for bringing clean drinking water on your river trip

Bringing water from home—or filling up jugs from a reliable source near the put-in—is the easiest way to ensure clean drinking and cooking water for a trip with plenty of raft support. (If you’re doing a self-supported kayak trip, you’ll need some filters.) Here’s a rundown on carrying water on raft trips:

  • Consider the amount of sediment in the river. Many of our favorite rivers, such as the Colorado and the Green, have heavy amounts of sediment, which can tax any water filtering system. For these trips, bringing water in large jugs is the right call. In some cases, you’ll be able to filter water from a clear-flowing tributary (for example, Rock Creek is a great spot to filter water when you’re in Desolation Canyon), but for big, sandy river trips you should plan to bring enough water for the entire trip.
  • Calculate the amount of water you need. You’ll need at least a gallon per person per day for a hot summer trip, assuming that most dinners will also require a large pot of water for cooking rice or pasta. Also coffee.
  • Choose your water jug wisely. This is a classic cost-vs.-quality calculation. Water jugs get bounced around in vehicles, dropped on rocks, knocked off tables, and otherwise abused on river trips. Although a sturdier jug will certainly last longer, for some river trips you simply need a lot of them and paying $60 versus $20 per jug is unpalatable when you’re buying 16. Here are a couple of types to consider:
    • Scepter Water Container: If you’re going for longevity, consider Scepter water jugs, which are BPA-free and made of food-grade polyethylene—they feel sturdy in your hand. However, without modification the spout is hard to pour from. You can add the Scepter Water Contain Spout for easier dispensing. Scepter containers’ claim to fame is they are made to military specifications: If the price gives you pause, check your local military supply store. We have a few of these supply-store finds (in black, so the water gets hot quickly on desert trips) that have been going strong for decades.
    • Reliance Aqua-Tainer: We have a few of these, and their main upside—besides the price—is the handy spigot, which tucks into the container for transport. 
Inexpensive water jug with a convenient spigot—dented but still doing the job on Grand Canyon

Other tips for choosing water containers for river trips:

  • Ensure that it can travel with the spout end on top. If the spout starts to leak at any point, at least gravity will help keep the water in until you get to camp.
  • Know that water from any plastic jug tastes bad—despite claims from water container manufacturers to the contrary. Plus, the water from that jug is warm on a typical river trip. To make water more palatable for drinking—especially for kids—consider adding a pinch of Gatorade or Nuun or other such powder, which can also help prevent dehydration in general.
  • Look for water jugs with integrated lids. If any part of the lid is a piece that you screw off and set aside, that piece will certainly get lost at some point, rendering the jug unusable.
  • Make sure you have enough rafts to haul the water. For a party of 16 people for a 5-day trip, that’s 80 gallons of water, which will fill 16 five-gallon jugs. Where will you put those 16 jugs? Water is one of the biggest factors when we consider how much raft support we need. The good news is you can typically line up those water jugs under the front thwart of the raft: We typically assign 4 jugs to each raft. 
  • Keep one jug accessible during the day. One of the last bits of business before you leave camp each morning is to refill water (and coffee!). Once all those personal water bottles are filled, make sure that one water jug remains relatively accessible during the day (not buried in the back of a raft under dry bags) for intermittent fill-ups. If you have a designated lunch stop, get the water jug off the raft and make it easy for people to fill up.

Choosing and using water filters for your river trip

Even if you’re bringing water with you, you need a water filter or two as backup or to supplement your water supply if you’re limited on raft space. Having water filters on hand gives you some options if a container starts to leak, water gets spilled (make sure to screw those lids on tight), or you lose containers in a flip. As part of your trip planning, identify the best sources of water for filtering on your trip and plan to stop at those spots: Aim for clear tributaries so you don’t exhaust the filter with heavy-sediment water.

Gravity water filters

Gravity water filters are easy to use and filter the largest amount of water in the shortest amount of time, so they’re a great choice for large, multi-day river trips. You simply fill the reservoir with river water, then hang it from a tree branch and let the water filter into a water jug or bottle. This beats pumping water hands down. I can’t think of any reason to use a pump filter on a river trip when you could let gravity do the work. A few tips for choosing a gravity water filter:

  • Go for the biggest filter you can find so you can fill those five-gallon water jugs as quickly as possible. Both the MSR AutoFlow XL Gravity Filter and the Katadyn BeFree Gravity Water Filter have 10-liter versions, the biggest we’ve found. Although we haven’t used the Platypus GravityWorks, it has great reviews and includes a secondary clean-water reservoir (although we find it easier to just filter into a 5-gallon container—less water transfer means less spillage). The Platypus has a 6-liter reservoir but filters at 2.75 liters per minute.
  • Check the typical water flow and study the filter system so you know how it works. The MSR AutoFlow filters about 1.75 liters per minute, and the Katadyn BeFree filters about 2 liters per minute, according to the manufacturers’ information. If you’re not getting that flow, make sure that your filters aren’t spent and you don’t have big chunks of sediment blocking the filter. The MSR AutoFlow has a sediment trap at the bottom of the bag, so make sure that is clear. 
  • Look for a filter that easily connects to your water container. The MSR has a connector that fits onto a wide-mouth water bottle or jug. The Katadyn has a small plug that can slide into any sort of container. 
Hang the filter high to capitalize on gravity

Water bottles with filters

In addition to a hanging filter, it’s wise to have several water bottles with integrated filters on hand for various uses:

  • For quickly filtering water if the big jugs are buried in the raft load during the day
  • For kayakers and stand-up paddlers to carry with them, especially on self-supported trips (no rafts)
  • For general back-up purposes

The beauty of water bottles with filters is you can replenish your water supply throughout the day. But the same downsides of filtering water with heavy sediment still apply. Paddlers using water bottles with filters as their only water source will want to double-check the capacity of their bottle filters and make sure they have enough to last the trip. 

Here are a few tips for choosing a water bottle with a filter:

  • Look for a bottle that filters for viruses as well as bacteria and protozoa. The Grayl Ultra Press uses a press filter that filters norovirus, rotovirus, and hepatitis A, making it suitable for use around the world. Other manufacturers make water filters that work on viruses, but not in a bottle format. Epic Water Filters’ Epic Nano pitcher filters viruses, so it could be a good choice for serving drinking water in camp but otherwise not a great format for river trips. 
  • Find one with a loop for attaching the bottle to your boat. Most water bottles for camping have loops, but it’s a pain if they don’t. 
  • Consider a bottle with a straw. Straws make it easier to drink faster (great for kids). The LifeStraw Go Filter is one of the few water bottles with filters that includes a straw. Bonus points: It comes with a carabiner so you can easily affix it to your boat.
  • Look at collapsible bottles if you’re low on space. This Katadyn BeFree is a good option. Although it doesn’t have a loop, it would be good to stash in an IK or hard kayak or to have on hand in a dry box. 

Again, if you’re headed to a river where you know norovirus or other viruses are a problem, stick with the Grayl system. But if that’s not a concern, the other choices will work for screening out common bacteria and protozoa. 

Grayl Ultra Press
Grayl Ultra Press

Compact straw filters

As a backup or emergency option, consider throwing a couple of compact filters into the load. Useful on side hikes where water supplies don’t last or for carrying in small boats, these micro filters are meant for drinking straight from the water source or decanting into a small vessel. Two to consider:

LifeStraw Peak Series straw is light and inexpensive, great as a backup or for side hikes

Water purification chemicals

If you know you’re headed to a river where viruses are present, bring along some water purification chemicals, which typically come in tablet form. Most tablets need to be added to water a few hours before drinking, so you’ll need a system for figuring out which water containers have been treated and ready to drink. We use short cam straps of different colors on the water jug handles to indicate whether the water is safe or unsafe.

Here are a few water purifiers that remove viruses (this list doesn’t include purifiers, including iodine, that don’t eliminate cryptosporidia):

Keep your drinking water safe on your river trip

Of all the safety concerns of a river trip, providing clean drinking water should be tops on the list. But with the high-tech filtering options available now—in addition to a good old jug for bringing good water from home—a little precaution will keep stomach bugs at bay for your river party. 

Dogs and water filter on river bank
Dogs wondering why all the fuss about water filters