Flash floods in steep terrain, explained: rain, rock and runoff
Why steep, narrow valleys turn heavy rain into sudden floods: stalled storms, thin soils, fast runoff, the forecast terms to know and how to stay safe.
Streams, skies, wild places – and how to read them
Hollow & Headwater is an independent journal for people who like to know what is going on in the creek behind the house, the haze over the ridge and the meadow at the edge of town. Our five writers cover water, air, wildlife, the outdoors and greener everyday living in plain language, with the sources linked.
Current Briefs See the whole journal ›
Rail-trails and the small-town comeback along old railroad grades
How abandoned railroad lines became trails, why some trail towns thrive while others stall, and a practical checklist for riding a long rail-trail well.
Brownfields explained: how old industrial sites get cleaned up and reused
What makes a lot a brownfield, how site assessments and risk-based cleanups work, what old sites become, and the questions neighbors can ask along the way.
From the journal
Heat pumps in cold mountain valleys: what works and what to watch
Cold-climate heat pumps can heat a house in a frosty valley. Here's how they work, what COP means, and how to site, size and back one up in the mountains.
Where your recycling actually goes after the truck pulls away
Follow a bin of cans, boxes and bottles from the curb through the sorting plant to new products, and learn which habits keep your load out of the landfill.
Hellbenders, mudpuppies and other giants of North American streams
Meet the hellbender, North America's largest salamander, and its big relatives: how to tell them apart, how they live, and why they need clean water.
Algae blooms in rivers: green mats, toxic scums and golden algae
Why summer rivers grow green mats, how to tell plain algae from toxic cyanobacteria and golden algae, and what the signs mean for swimmers, dogs and anglers.
Backyard composting without the smell: what each odor is telling you
A healthy compost pile smells like damp soil. Ammonia, rotten eggs and sour vinegar each point to a specific problem, and most can be fixed in one afternoon.
Paddling small rivers: how to read a stream gauge before you go
Stage, flow, trend and lag time: a step-by-step way to read a stream gauge and tell whether a small river is too low, about right or too high to paddle today.
Browse by theme
- Water & RiversStreams, rivers, wetlands and groundwater – how to read them, enjoy them and keep them healthy.
- Air & ClimateSmoke, ozone, weather, a changing climate and the air inside our homes, explained in plain numbers.
- Conservation & WildlifeHabitat, native plants, birds, amphibians and the work of keeping wild places wild.
- Sustainable LivingHome energy, waste, gardens and everyday choices – practical, honest about costs, free of greenwash.
- Outdoor RecreationHiking, paddling, seasons and safety: getting outside and coming home with good stories.
- Science & ExplainersHow the natural world works – from soil chemistry to storms – explained without the jargon.
- Community & LifestyleTowns, people, food, travel and the everyday life that grows up around land and water.
Field guides
Field AlmanacWhat is blooming, spawning, migrating and turning colour, month by month.Maps & DataHow to read the public stream gauges, air maps, wetland and soil maps yourself.Green TipsSmall, honest habits for the home, the garden, the trail and the river.
- Air quality at home: particles, ozone and cleaner wood smoke
- Kick-net stream monitoring: technique, bug groups and simple scores
- Erosion and sediment control on building sites: what good looks like
- What an impaired stream means: 303(d) lists and TMDLs, explained
- How a watershed assessment works, from creek chemistry to land use
- Inside an environmental lab: why water test results can be trusted
- Shale gas and water: wells, wastewater and what is still debated
- Illegal dumping and roadside trash: why it happens and what helps