Earlier this summer we were living in severe drought – running out of grass and hay for livestock, top soil blowing away in the wind, bare ground, dying trees, rampant wild fires, and a tiny trickle for a river.
Now a few months later we have a whole new set of challenges — bridges damaged, roads caved in, homes flooded, debris spread all over, people stranded, electric and phone lines damaged, and deep erosive cuts in the land. We are all sharing this struggle with the increasingly extreme forces of nature.
An Optic article reprint describing the 1904 Las Vegas flood offered parallels but distinct differences from our recent flood. Both situations involved numerous days of rain followed by a flood. In 1904 it amounted to 5 inches of rain resulting in 11,600 cubic feet per second stream flow, this year it was over 6 inches of rain with just over 1,500 cfs. I’d speculate the significant difference in stream flows is related to the condition of our watershed at the time.
By all accounts, at the turn of the century, the Gallinas Watershed was severely logged and over-grazed to support the railroad and growing population. With a considerable lack of plant cover, especially in riparian areas, to help hold rainfall, the Gallinas yielded a stream flow about seven times that of our current comparable storm. Since 1904 considerable healing has occurred in the Gallinas, to the credit of landowners and managers who have improved land stewardship practices.
Forests have re-grown, riparian areas are again growing willows and cottonwoods and meadows have good grass growth. This healing is all but complete; we still have a ways to go if we are to weather larger floods, especially those that are likely after a large fire.
People have asked me — What can we do about this? Are we limited to responding to emergencies? Is there any way to pro-actively address the continuing threats of flooding, fire and drought? Sometimes it can seem like these things are just bigger than we are.
The good news is that there is work we can do to further the restoration of our watershed which will both reduce the effects of the drought and minimize the impacts of future floods — providing a more secure water supply at the same time.
When it is in a healthy functioning condition, our watershed can provide the essential services of flood abatement, water storage and water filtration. I offer four steps we can take to help our watershed moderate the extremes we are faced with:
1. Restore healthy stream channels by reconnecting them to their floodplain. Rivers and streams need access to their floodplain where flood waters and floating debris can spill over the banks and spread out. These dissipated flood waters can better infiltrate the soil and later replenish rivers and aquifers, increasing water flows during drought periods. A long history of floodplain developments coupled with straightening and entrenching river channels has disconnected our river from its normal floodplain and increased the severity of downstream floods. Restoration is only feasible in areas with little to no development in the Gallinas floodplain, but if accomplished in all viable areas, would help relieve flood severity downstream.
2. Restore and maintain abundant plant cover on all lands. When abundant plants cover the ground in our watershed, each plant helps to hold soil in place, preventing erosion. Then each plant helps carry water into the soil where it is stored. This is a huge service provided by millions of plants covering the ground. We have all seen bare dirt during heavy rains with water rushing over the surface, carrying with it precious top soil and worsening downhill floods.
3. Restore and maintain healthy bosque vegetation (e.g. willows and cottonwoods next to streams). Abundant bosque vegetation holds stream banks together, filters sediments, traps debris keeping it out of rivers, and further helps surface water flow to penetrate into the soil. Water stored in the soil does not evaporate and is available for a long time to grow plants and replenish the river.
4. Restore, protect or recreate wetlands. Abundant wetlands adjacent to rivers help capture and store flood waters and sediment. In a wetland that stored water is purified, then slowly released to the river and underground aquifers, further lessening drought conditions.
The work to restore these healthy features to our watershed is very doable — not as costly or difficult as the infrastructures to do the same work – and would improve the quality of life for our community at the same time. The importance of prioritizing the work to put our watershed back in full working order is clearer now that we have seen the hardships of one that is not.
Although restoration is a community effort, a Comprehensive and Collaborative Gallinas Watershed Plan is needed to guide this restoration and management of our watershed and to help us prepare for, respond to, and reduce the effects of fire, flood and drought.
Lea Knutson is the executive director of the Hermit’s Peak Watershed Alliance. She may be reached at email@example.com