water resources & hydrology of Zawiya Ahansal within the High Atlas Mountains of central Morocco

An account by Tom Osborne, HydroSolutions Vice President and Professional Hydrologist 

In May 2016 I was invited to Morocco as a water specialist by the Atlas Cultural Foundation (ACF) and Atlas Cultural Adventures to assess water resources and hydrology of an area within the High Atlas Mountains of central Morocco known as Zawiya Ahansal.

Zawiya Ahansal is a remote and mountainous region located between 5,000 and 12,000 feet in Morocco’s Central High Atlas Mountains. It is a high desert region with temperature extremes in June and July ranging between 32 and 100 F. Accumulating snow in the high country feeds perennial springs and streams. Equivalent terrain in the US would be the City of Rocks in Idaho and southern Utah.

The founder of ACF, Cloe Medina Erickson, wrote this about the area:

The roadless Zawiya Ahansal region of Morocco’s central High Atlas Mountains is named after Sidi Sa‘id Ahansal, a local 14th-century religious teacher believed to be a descendant of King Idris I of Morocco and the Prophet Muhammad. It has been a crossroads for travelers and a place of seasonal migration for centuries. The historic trade route from Timbuktu to Marrakesh passes over the rugged plateaus and deep limestone gorges that dominate the landscape, crossing eastward from the Atlantic plains over the Atlas and into the Sahara. With an elevation above 2000 meters (6500'), the plateaus are covered in deep snow in the winter, leaving only the gorges with their springs, forests and irrigable land capable of supporting permanent habitation. In the summer, however, the snow melts to reveal fertile pastures, an irresistible invitation to the nomadic pastoralists who spend their winters in the desert regions south of the Atlas.

Source: Erickson, Cloe. “New Nomads of the High Atlas.” Saudi Aramco World. March/April 2008: 24-29. 

Having made five water mission trips to Uganda in recent years, I was immediately excited about the prospect of visiting an entirely different region of Africa, and I was most definitely not disappointed.

I arrived in Marrakech on May 24 after a 21 hour plane trip. Although only the Strait of Gibraltar separates Europe from Morocco, Arabic language and African culture quickly signaled that I was out of Europe. It was a six hour car ride across the lowland desert and over two mountain passes to get to our hotel in the village of Amezray. The Dar Ahansal is a great little hotel nestled into the hillside, and like every building there, artfully constructed of native stone. The operating managers Said and Fatima serve three hearty meals each day and will pack a stout lunch for the numerous foreign trekkers that launch their trips from here. 

The first day and a half were dedicated to introductions and orientation. It was pretty clear that my work here would be dictated by the remote and difficult terrain, along with the usual adaptation to local customs. Morocco is an Islamic monarchy and the dress code in the countryside dictates that females and males not show their knees or elbows.

I was anxious to meet the couple who left western civilization (meaning Bozeman, Montana)  in 2005 and built their life in this remote corner of Morocco.  Cloe and her husband, Kristoffer, appear to have found a harmony between her attraction to Eastern architecture and culture and his affinity for extreme mountaineering and photography. In the understated way that high achievers of this generation navigate life, these two young people are already legendary adventurers.  They built a beautiful house of native stone overlooking the Ahansal River valley in the village of Aguddim.  Actually nearly every house in these villages is set on the hillslopes overlooking the valley, but their home is a perfect blend of traditional construction with western-style size and titivations.

By the time I arrived, MSU Professor of Architecture, Chris Livingston, was there with his group of students, working on their “design-build in an exotic foreign country” experience. Chris was the ACF contact who prepped me on the water needs and conditions of the area. Chris and his students work on very practical, yet critical projects: a solid waste incinerator, off-stream laundry wash stations, water “chateaus” (storage/distribution stations) and drinking fountains for people and donkeys. These are basic infrastructure projects that are leading people here to improved health and environmental stewardship.

As a strange guy in a strange place, if I was going to conduct any serious field hydrology, I needed a guide. Fortunately for me, I got someone who has been to this region on four previous trips, is a proficient backcountry enthusiast, is a trusted colleague of mine on trips to Uganda, and a person who could save my life if need be- Leigh Taggart, R.N., MPH. with over 20 years experience in ICU and Emergency medicine. Leigh and her husband, Matt, live in southern British Columbia, but maintain a part time residence south of Livingston, MT. Leigh also happens to be a board member and the Public Health Director of ACF. Since she has been to all of the water sources of interest on this trip, she was able to lead me directly to each of these remote locations. She promised me there would be a lot of adventurous hiking, and she did not disappoint.

The primary purpose of my visit was to conduct a preliminary assessment of the principal water supply sources of the region, which consist of springs and streams fed by springs. The mission of ACF includes health education and environmental stewardship. The link between clean water supplies and the wellbeing of the local populace is nowhere more center stage than in Africa. Getting to the springs and selected stream locations meant anything from a moderate hike (1 – 5 km) to an overnight backpack (25 km). After some orientation to the terrain and spring locations, it became obvious that there are small springs (2 - 10 liters per minute) at high elevations emanating from local perched aquifers in the layered Jurassic sedimentary rocks, and there are larger springs (1,000 – 20,000 liters per minute) that discharge from mountain-front fault systems into the principal river valleys.

I was shocked to be told that the first spring we visited, which was a perched spring above the town of Aguddim, was, until a couple years ago, the sole source of water for about 1,500 people. It had a measured discharge rate of 8 liters per minute.  While the quality appeared excellent, this amounts to only 7 liters per day per person, assuming all water could be used. In reality there were severe shortages. Recently, the government invested in a new central water system that pumps and treats water from the Ahansal River, so the supply is much better. Each house is metered and the cost ranges from 3 – 7 Dirhams per metric tonne, roughly averaging $2.00 per 1.000 gallons. My January water bill in Absarokee worked out to $15.45 per 1,000 gallons.

The morning of May 28 broke early. This was the day Leigh and I were to hike the trail to Taghia, the most remote of the villages in the Zawiya Ahansal region. For the next six hours we traveled a well-worn trail ascending the canyons and breaks carved by the Ahansal River. The scenery and geology were spectacular. Faults, thrusts and massive-amplitude folds in the sedimentary strata were jumping out at me around every bend. The resident farmers carved out irrigated terraces along the narrow valley edges. Leigh mentioned that this place reminded her of Nepal where she has been on trekking adventures.

Taghia is in my book, the quintessential exotic destination. Accessible only by foot or pack animal, it is the end of the regular trail and at the base of soaring limestone cliffs that rise 700 meters or more. Beyond this point you better be a highly experienced mountaineer or canyoneer. We checked into the Gite Said, one of the small hotels in town and set out to find the head of the canyon and the origin of the Ahansal River.

You can’t imagine a more dramatic setting for a major spring. The water issues from a series of near-vertical fractures in the limestone mountain front about 30 meters above the base of the canyon. Immediately above the springs the valley reduces to a tortuous slot canyon that disappears into the rock mass. With a temperature of 12.5 C and Specific Conductance of 343 µS, the water was of excellent quality. With some difficulty, Leigh and I found a place to gauge the coalesced flow of spring water as it emerged from the shadows of the canyon. 

The stream created by the main Taghia springs was about 4 meters wide at this spot. We measured the width and depth of our selected section at 33 points along the tape measure. I brought a large tub of water testing kits and meters with me, but could not readily fit a current meter and wading rod. Thus, we resorted to the age-old method of velocity measurement using a surface float- in this case a Moroccan orange. Leigh ran the stopwatch and recorded while I placed and caught the orange at each subsection.

While we were laboring through the measurement an older Moroccan man in a traditional robe saw us on his way to or from the spring. He evidently became fascinated with the unusual spectacle and sat down to watch us. I was using a small bucket to catch the orange after each velocity measurement, but one time I missed it, and the orange was swept into the chute immediately below and quickly disappeared downstream. To our amazement, the Moroccan man sprang up as if he was on fire, jumped the stream and ran-hopped over the large rocks down thirty meters or so, and scooped out the orange. He unassumingly returned the orange to us as if we had employed him to do just this, and resumed his seat to watch us finish. We did so, and then I proudly presented the orange to him as a token of his unsolicited kindness. The spring flow turned out to be 0.113 m3/sec, about 4.01 ft3/sec.

That night dinner was served community-style and we got to share it with a group of climbers, from France, Spain and Belgium. These guys, and one gal, evidently hang out there for days, maybe weeks, and climb the incredible array of walls and massives in the immediate area. On the bookshelf was a climber’s logbook, with handwritten sketches of climbing routes.

The next morning we packed up and paid 120 Dirhams each for room and board- roughly $13. We hiked a trail from Taghia north up a ridge about 2.5 km, then down the other side another 3.5 km to the village of Tighanimin, and finally up the valley another 2 km to the main Tighanimin Spring. This spring was a small feature and emerged from the dry riverbed alluvium. It clearly is not a regional discharge spring. We measured it with a bucket and stopwatch at 83.6 liters per minute (22.1 gpm). This is the one and only water source for the village of about 1,500 people, along with the irrigation of gardens and terraces along the valley.

We finished there about 3:15 pm and then had the long hike back to the hotel on a main trail, about 13 km. The trail scrolled down and up along the north valley wall affording idyllic views of the irrigated green terraces and massive rock outcrops backlit by the setting sun. The people we met were all smiles, pointing us to the best footpath among the web of trails. Most of the children were playfully curious. A few along the main trail are accustomed to foreign trekkers and ask for candy, hair ties or money. We arrived at the hotel just before 7:30 pm. So, altogether it was an 11-hour day of hiking about 21 - 22 km (13-14 mi) over pretty rough terrain to get one spring flow measurement. It was a fabulous couple days of what I’ll call “extreme hydrology”- in case there is ever that sort of reality show.

My last full day in Zawiya Ahansal was dedicated to measuring the discharge of the main Ahansal River spring above the village of Aguddim. No one I asked recalled that there have been any previous measurements of this spring. But since life in this valley would not exist without it, I would be surprised if it hadn’t been measured at some time in history. The spring issues primarily out of the streambed of the river, on both banks, forming a distinct channel on the north side, but immediately mixing with the upstream river water on the south side. The only way to measure the total was to gauge the river upstream and downstream of the springs.

Leigh and I got much needed help in this effort by Kris Erickson, and his father and brother who happened to arrive for a visit the day before. The river on the downstream side was 11.4 meters wide, averaged about 22 cm in depth and had an average surface velocity of 0.88 m/sec. We measured the width, depth and velocity of 27 subsections, again using the “orange float” method to obtain the surface velocity. I applied an adjustment factor of 0.87 to adjust this to the average profile velocity. The total river flow below the springs was 2.0008 m3/sec (70.7 ft3/sec).

We next walked several hundred meters upstream of the spring to a stable cross-section and gauged the river flow. At this section the width was 4.05 m, average depth 12 cm, and average surface velocity of 0.454 m/sec. We measured the width, depth and velocity at 26 sub-sections, obtaining a total discharge of 0.1873 m3/sec (6.614 ft3/sec) after applying the velocity correction factor.

There was a cement irrigation structure that diverts water directly from the main spring which also had to be measured and added to the total flow. This channel had a fixed width of 60 cm, average depth of 17.13 cm, and average surface velocity of 0.368 m/sec. The total adjusted discharge was determined to be 0.0435 m3/sec (1.54 ft3/sec).

The difference in the Ahansal River flow plus the irrigation diversion gave a total discharge for the main Ahansal River Spring of 1.857 m3/sec (65.58 ft3/sec).  The estimated accuracy of our measurements were probably in the range of +- 10 - 15%. Everyone knows that the river dramatically increases in size due to the spring discharge, but most people were surprised to learn that the flow increased 11 times. I believe that the main Ahansal River Spring is a regional groundwater discharge feature that transcends the local watershed boundaries. However, at this point, I do not know from which aquifer/aquifers it discharges. Also, I can’t rule out the possibility that streamflow from the upper Ahansal River is lost to seepage and reemerges here, but I think that unlikely based on the pristine quality of the water.

Leigh and I finished the day with a hike up the ridge south of the main spring to visit the area of a historic lead mine. We performed field water quality measurements on a small perched spring about 220 m above the river level. We were treated to a vivid outline of the village of Aguddim as the setting sun backlight the Igherms and houses.

The next day, June 1, I read the last of the E. Coli sample results and packed up. Leigh and I left for Marrakesh just after 0800 and arrived there about 1300. Lunch (with a beer) was at Mama Mia’s Italian Restaurant in the new section of the city. We were at the airport by 1430 and departed at 2120. I was relieved that I was able to get all the water quality test kits there and pack home some water quality samples for laboratory analysis. The flight left Marrakesh at 2120 and arrived in Amsterdam just after midnight. After a short overnight stay at the hotel in Schipol Airport, I had a long uneventful flight back to Minneapolis and then Helena. Angie and the three “Ozzie” granddaughters were there to welcome me home with a big decorated cardboard sign. No matter how great the trip, there’s nothing like coming home.

There was a lot packed into my relatively short trip there. Next, I need to prepare a summary report and include all the hydrologic data we collected. I want to extend my deep appreciation and thanks to ACF for their sponsorship of my trip, to Cloe and Kris Erickson for their personal attention to my schedule and needs, to Said and Fatima at the Dar Ahansal Hotel for the warm hospitality, daily fresh food and drink, and enjoyable room, to Ayoub Amrosaid and the staff of ACF for all the behind the scenes coordination, and to Leigh Taggart and Chris Livingston for their willing and able participation in the hydrologic work.

Tom Osborne

HydroSolutions Inc

Billings and Helena, Montana USA