The Ditch - Headwaters

In the year of the American Revolution, before there were dams or modern roads to confuse one’s sense of geography, Fray Francisco Atanasio Domínguez visited the church at Santa Cruz as part of a general review of their missions by the Franciscans.

He noted the village was near a “river, which, although it arises in the aforesaid sierra from three not very large springs, is joined from very high up by three or four rivulets which feed it more water than it brings from it source, and therefore it is permanent.”

The sources are today called the Río Frijoles and Río Medio which join before the river enters Santa Cruz Lake, and the Río Quemado which joins soon after it escapes impoundment.

The Picuris-Pecos fault that Patrick Sutherland says occurred during the Laramide Orogeny when the Sangre de Cristo were being formed the last time defines their origins to the east. On its west side, the fault thrust Precambrian rocks of the Ortega Formation over existing Pennsylvanian strata to the east. Embudo granite exists to the west.

The Jicarilla Fault, which dips in the opposite direction, lies a few miles to the east. It also appeared in Laramide times and now separates the Pennsylvanian from the Precambrian quartzite of the Truchas Range.

The Frijoles arises before the Picuris-Pecos Fault and curls south and west through the widening Panchuela West.

The origins of Río Medio lie farther north and east in the watershed before the Río Grande and Pecos known as Trailrider’s Wall that runs from Truchas Peak to Pecos Baldy. From there it crosses both the Jicarilla and Picuris-Pecos faults.

Río Quemado begins east of the Picrus-Pecos fault, with the south fork coming from somewhere between Middle Truchas Peak and Truchas Peak. The north fork leaves a glacial cirque near North Truchas Peak and falls 100' at the Quemado Falls.

All the mountain rivers are accessible to hikers and fishermen who aren’t intimidated by Forest Service warnings that a trail is not only difficult but hard to locate.

For common folk, the last you see of the Frijoles is in a valley that lies some 75' below route 503. Settlers in Cundiyo have dug ditches from the curving river to water what look like flattened hay fields.

The Medio is less visible as it wanders along the edge of a privately owned meadow just north of the confluence with the Frijoles. Even fisherman can’t get through there.

Río Quemado is hidden by the settlement of Cordova and by scrub that’s grown along its banks, but, away from the road, flows there through a fairly broad valley.

This is as far north as I can follow the Santa Cruz, and it’s as far north as settlement had penetrated when Domínguez counted 125 families living in the village of Santa Cruz, 71 in Chimayó after the confluence, 52 in Quemado and 26 in Truchas just beyond.

Notes: Francisco Atansio Domínguez. Republished 1956 as The Missions of New Mexico, 1776, translated and edited by Eleanor B. Adams and Angélico Chávez.

Photographs:
1. Río Frijoles as it joins the Rio Medio, 14 February 2012.

2. Río Frijoles below 503 east of Cundiyo, 16 February 2012; the river is marked by the red willow; the differences between the near hills and the Sangre de Cristo may be marked by the differences in vegetation in back.

3. Río Medio just before its merger with the Río Frijoles along route 503, 14 February 2012.

4. Río Quemado at Cordova just off county road 83, 21 February 2012.

The Ditch - The Dam

The Santa Cruz dam sits near the edge of an uplift of Mesoproterozoic granite topped by early Pleistocene sandy gravel.

Daniel Koning’s geological map for the Cundiyo quadrangle shows the uplift lies between two north-south faults with the western one through the reservoir and the eastern roughly along route 503. Both are moving east. Between them, northeast of the lake, is another, shorter fault that curves and is moving northeast.

The sedimentary land at the top of the dam basin is 6300'. The structural and hydraulic heights of the dam are 151' but only 100' is available to hold water. The width of the dam at its base is 103.6'. That means the crack in the uplifted rock, at its narrowest, is something like 150' x 100'.

The lake covers 121 acres at the top and looks to be roughly 4000' long from the face to the point where the bowls narrows and water is white in the picture below. The opening widens to 600' in places.

From there the Santa Cruz river runs for a mile to the point it forms at route 503. It first goes south where the land above is 6400', then curves to go northeast where the surface land is 6600'. It flows through what Craig Martin describes as a “narrow, rocky canyon.”

The 10' to 15' wide river has “shallow runs and many holes 4 to 10 feet deep” for brown trout. That means, the the crack goes more than 10' below the surface and the river bottom is rock fill.

Martin say’s it’s possible to walk the river, nearly to the dam, if you’re willing to wade through the water and navigate those openings.

You don’t need to venture so far to see the rocks that form the walls of the reservoir. They’re visible on route 503 where the river begins it narrow journey. Daniel Koning says the granite and granitic pegmatite have a “distinct reddish weathered surface” and consist of potassium feldspar, quartz, muscovite, plagioclase feldspar and biotite.

Outcrops can also be seen when you follow the river back from route 520 to the dam at the northern end of canyon fault.

The Bureau of Reclamation says that the “quality designations” of the dam’s supporting rock “ranged from poor to very poor; however, with depth the fractured zones are locked in and will provide adequate foundation.”

That’s as reassuring as it gets in an area striped with faults. A collapsed dam would spread disaster all the way to the Rio Grande.

Notes: Martin, Craig. 2002. Fly Fishing in Northern New Mexico.

Photographs:
1. Santa Cruz lake and dam, 14 February 2012.

2. Santa Cruz dam from the other side, 16 February 2012.

3. Santa Cruz lake looking towards the north opening, 14 February 2012.

4. Walls of the Santa Cruz river canyon from route 503, 14 February 2012.

5. Santa Cruz river from route 503, 14 February 2012.

6. Exposed rock on route 503, 14 February 2012.

7. Exposed rock from other side of dam, near route 520, 16 February 2012.

The Ditch - Chimayó

When you pass beyond the badlands, the land opens out. You’ve passed the northeast trending boundary between lithosome B from Peñasco and lithosome A from the Santa Fe section of the Sangre de Cristo within the Tesuque formation. Ridges of sediment still exist to the north, but they’re farther back from the road, on the other side of the Rio Chiquito. They’re now Quaternary alluvium.

The road no longer follows the Santa Cruz which lies farther to the right. The 1940 WPA Guide to 1930's New Mexico says the area then was “planted with fields of corn, chili, frijoles (Mexican or pinto beans), apple and peach orchards.” Today all you can see are houses, many announcing themselves as studios or galleries.

Here and there signs warn of possible water on the road. When you look north, you often see an arroyo that’s been turned into a road.

On the other side of the road you see steeply declining roads where water runs from arroyos and route 76 itself.

Dams were built on several of these washes in 1962, to stop silt from running into the Santa Cruz and the irrigation ditches downstream. In Sabrino’s Map, Don Usner suggests they may have had the unintended consequence of encouraging settlement along the arroyos. He says early settlers in Chimayó “took care to build their homes well away from the arroyo beds” where “spectacular floods once churned,” but since the dams were built “random arrangements of mobile homes lay boldly in the path of some of the temporarily constrained washes.”

You don’t actually see the Santa Cruz again until you turn towards the Santuario in El Portrero southeast of the old Chimayó plaza. For the most part, the rocks again are smaller than they were downstream.

In front of the dam face, the river is dry or nearly so. The dam is releasing no water right now.

Between the two points, the Rio Quemado has joined the Santa Cruz and snow is continuing to melt from the recent flurries.

Photographs:
1. Rio Santa Cruz in El Portrero, west of the Santuario on route 520, 16 February 2012.

2. Arroyo to north off route 76 in Chimayó area, 16 February 2012.

3. Road leading off 76 toward Rio Santa Cruz in Chimayó area, 16 February 2012.

4. Rio Santa Cruz in El Portrero, west of the Santuario on route 520, 16 February 2012.

5. Rio Santa Cruz soon after it leaves the dam, off route 520, 16 February 2012.

6. Snow melting into Santa Cruz river from route 503, 14 February 2012.

The Ditch - Quarteles

My plans to get a better idea where the local acequia ran below the great mound by walking the nearby farm road were dashed by the realities of life in New Mexico in February. Light snow began falling in the night and heavy clouds persisted through the morning. With no sun until noon, it was too cold to walk in mid-morning when the local paved roads are safest for pedestrians.

I retreated to my car to seek the Santa Cruz dam. As you go east you drive through three zones. The first begins as you enter Quarteles where the USGS map says the elevation is 5757'. You rise 150' to the area where suburban Chimayó begins. The elevation there is 5909' and rises to 6220' where you make the turn for the Santuario. Continuing east, the road rises another 280' before the exit to Santa Cruz Lake.

The elevation increase in the first stage is emphasized by the badlands on the left which can be 50' higher than the road. At their base, there are the familiar Tertiary sediments of the Tesuque formation lithosome B that came from the Peñasco embayment. On top, according to Daniel Koning, are glacial cobbles and pebbles composed of quartzite, granite and pegmatitic quartz.

At the point where the road from La Puebla meets route 76, the badlands rise from 5800' at the road to 5950' inland.

Across the road, the Santa Cruz river level is low, fed only by recent snow in the air and melting in tributaries below the dam. Banks of those cobbles lie exposed like beached whales, white in the winter light.

About three quarters of a mile farther down the road, the Placita Road meets route 76.

The land exposed by road builders is leaching cobbles.

Across the road, the Santa Cruz is flowing through and over the rocks.

Photographs:
1. Rio Santa Cruz at La Puebla Road near route 76, 16 February 2012.

2. Badlands at junction of La Puebla Road with route 76, 16 February 2012.

3. Rio Santa Cruz at La Puebla Road near route 76, 16 February 2012.

4. Badlands at junction of Placita Road with route 76, 16 February 2012.

5. Road cut on route 76 at junction with Placita Road, 16 February 2012.

6. Rio Santa Cruz at Placita Road near route 76, 16 February 2012.

The Ditch - Crossing the Highway

I know as much as I’m going to know about the source of our local acequia until I go to Chimayó to look at the mother dam. It’s time to return to where I last saw the ditch, below the highway and great mound, and start to find out how it gets from there to the far arroyo.

I returned to the parking lot with all the “do not enter” signs and began walking towards the ditch, on the outside of barbed wire.

I couldn’t get very close to the diversion point, but it was obvious as I neared the utility pole where the outlet existed.

I looked across the road at an odd cut in the mound.

When I got across the road, I could see where the water came over. Two culverts on this side of the road, two controls on the other.

From there the concrete lined ditch began its final journey up the mound.

I still have no idea how the water does that, and it’s the wrong season to go watch. I have to wait spring when the ditches are running to see how water runs uphill.

Photographs:
1. Local acequia below 84/285, 3 February 2012.

2. Gate and fence preventing access to the land with the ditch, 17 January 2012.

3. Ditch controls below 84/285, 3 February 2012.

4. Ditch path above 84/285, 3 February 2012.

5. Water outlets above 84/285, 3 February 2012.

6. Ditch heading up the mound, 5 February 2012.

River Rock

River rock is one of those terms used everywhere in the country that everyone knows what means and no one defines. Generally, it’s rock that has a relatively smooth surface. I say relatively, because its not as smooth as a polished tombstone, but it’s not jagged.

If you ask for something more specific, people take the adjective smooth and turn it into a verb. There the trouble begins, because they start to say things like “the erosive action of the moving water from a river smooths and shapes the stones. Other times, they say something slightly romantic like “smooth surfaces created by tumbling around in rivers for years.”

Maybe, elsewhere in the country. Here, even when the Rio Grande is running high, like it was in the above picture take last October under the Griego Bridge in Española, the water only creates rapids. You don’t see rocks being tossed about. More likely you see them laying outside the action where silt can filter through them.

Smoothing and polishing are not the same thing. The second is done by removing material, often by breaking large pieces into smaller ones. In a rock tumbler, the polishing is done by some kind of abrasive grit, something like silicon carbide, with water used as a facilitating lubricant, not as the active agent . The winds here move sand at high enough velocities to blast surfaces.

The above is a piece of granite I found in the area of the far arroyo this weekend. Part of it has striations that left a relatively smooth surface. The darker corner at the top in the picture below was untouched. There the smoothed section has a lighter color because the abrasion removed the tops of the softer, darker mica, but harder flecks of quarts remained.

The smoothing of river rocks is done by filling in rough surfaces with finer sand that drops when the river currents slow. It often is the same general material loosened by wind and deposited in the water. Eventually the sand becomes welded to the surface, like a rind.

I first noticed this with a bit of granite I picked up somewhere along route 554 north of Ojo Caliente last fall. You can see the brown outer skin is very different than the quartz and mica inner stone. If you look carefully, you can see the outer layer isn’t uniform in thickness, but penetrates in low edges to fill the rough places. That’s what creates the coarse textured, smooth feeling exterior surface.

If the river rocks were polished by removal, they’d look more like tombstones or the stone above. Instead, they look like amorphous potatoes. Round, formless, grey lumps.

Someone broke the above rock outside a near neighbor’s drive. Since he works for Cook’s Transit Mix, I assume the rock came from somewhere just north of Española. You can just see the lighter colored outer layer that built up around the granite, especially on the lower curve in the upper left had corner.

Last weekend my immediate neighbor had loads of sand brought into our shared drive by a friend of his who said it came from his yard in Velarde. A broken piece of granite filled with quartz and mica landed near my gate.

Again, you can see the boundary between pock marked grey shell and the uneven texture of the broken face. It may looked like it’s been smoothed by removal, but if you look closely you can see the uneven fill that protects the bright interior with a dull overcoat. In places it has even started to colonize the surface.

The Ditch - The Dam

I could see nothing more of the Santa Cruz river along 84/285, so I drove along the Santa Cruz road searching for some place the river was visible. I found it at the Branch Bridge on Route 106.

Upstream, it’s the obvious continuation of the river seen in town. Downstream, there’s a concrete faced dam that sends water off to the left where there are four gates. Three, closed now, divert the water into the local ditch. The other, at a right angle and open now, sends the water back into the river.

The water runs hidden in a culvert under the access road to emerge a bit downstream in a natural ditch shrouded by trees.

It continues in that dirt lined ditch for some feet until it approaches another concrete dam.

This is the true beginning of the ditch. When the gate to the right is down, water backs up in that dirt ditch until it reaches the slot in the concrete. At that point water enters the ditch proper.

When the ditch is not in use, like now, the gate is raised, and the water enters a canal that takes it back to the river.

In normal times the river remains as placid here as it is in town.

When water levels are high, especially when it rains in summer, the water first backs up into a spillway behind the dirt ditch.

Water can also back up behind the dam, as it must have done last summer.

This dam is relatively new. The Santa Fe New Mexican for 15 May 1989 said it had been dedicated that week and replaced an earlier earthen dam at the same location.

Photographs:
1. Santa Cruz river at the Branch Bridge, looking upstream, 27 January 2012.

2. Diversion gates on Santa Cruz dam, 10 February 2012.

3. Entry point for water from the dam into the transit ditch, 10 February 2012.

4. Control point of entry for the local acequia, 10 February 2012.

5. Control point of entry with local acequia reach downstream, 10 February 2012; the great mound facing 84/285 is just visible in the back.

6. Return channel for water not used in the local acequia, 10 February 2012; the tree has been cut and left blocking the movement of high objects into the Santa Cruz river.

7. Santa Cruz river downstream from the return channel, 10 February 2012.

8. Spillway for the transit ditch, 10 February 2012; the light bank in the center back is the hump separating this from the actual ditch. The culvert in #3 is under it.

9. Land between the dam and the river seen in #1, 27 January 2011.