Difference between revisions of "The Carmel River Watershed"

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== Timeline ==
 
== Timeline ==
 
Listed below is a brief timeline of water rights and dam operation in the Carmel River Watershed.  A more exhaustive timeline is availabe at [http://carmelriverwatershed.org/wp-content/uploads/2011/07/Carmel-River-History_final-amendedLMH.pdf Carmel River History].
 
Listed below is a brief timeline of water rights and dam operation in the Carmel River Watershed.  A more exhaustive timeline is availabe at [http://carmelriverwatershed.org/wp-content/uploads/2011/07/Carmel-River-History_final-amendedLMH.pdf Carmel River History].
* '''1883''' First known dam on the river created ½ mile below site of the current San Clemente Dam.
+
* '''
* '''1905''' To increase capacity, Pacific Imp. drills six wells near the lower end of Laureles Ranch, installs pumps
+
capable of drawing 2M gallons per day, and begins installing a larger pipe thru the valley and around the
+
peninsula.
+
* '''1919''' S.F.B. Morse forms the Del Monte Properties Co. and purchases Pacific Improvement Co.’s Monterey
+
holdings for $1.3M.
+
* '''1921''' Carmel River becomes site of several mining operations along the lower river, including the Carmel
+
River lagoon
+
* '''1930''' Morse sells water system to Chester Loveland.
+
* '''1931''' Loveland raises water rates. Proponents of a public ownership estimate the cost at $1.8-$2M to
+
purchase water rights. First debate over public, or private water, management.
+
* '''1935''' Public ownership of water supply defeated 2 to 1.
+
* '''1939''' CW&T provides water to 7,430 Peninsula customers, irrigates 5 golf courses and services a growing
+
sardine cannery industry.
+
* '''1947''' San Clemente Dam is 25% silted. A filter plant opens near San Clemente Dam, improving water
+
quality. CW&T releases plans for the Los Padres dam, along with other improvements. Total cost $1.4M.
+
Application for 19,000 af per year storage capacity was objected by steelhead fishermen and farmers. SWRCB
+
grants 6,000 af per year and limits season of diversion to 10/1-5/31.
+
* '''1953''' Flood event. Rainfall at Los Padres dam was 2.11 inches in 24 hours and Carmel Valley received 1.48
+
inches.
+
Carmel Valley residents compare the 1958 flood to the 1995 and 1998 floods.
+
* '''1959''' Monterey Peninsula Water Mgmt. District initiates efforts to buy out CW&T.
+
* '''1965''' In the September election, the measure was defeated 10,766 to 3,053. Loveland sells CW&T to
+
American Water Works Company.
+
* '''1966''' American Water Works Company creates California-American Water Co. to manage the operations of
+
CW&T systems.
+
* '''1970''' Cal-Am announces Peninsula water shortage. Current use is at 15,000 af per year. Cal-Am proposes a
+
dam in two stages.
+
* '''1971''' Cachagua dam project abandoned. A new San Clemente dam is proposed that would create a 40,000
+
af reservoir and yield 21,000 af per year. Army Corp. of Engineers recommends a flood control component
+
versus the original dam.
+
* '''1977''' Monterey Peninsula Water Management District is created to augment, protect and manage water
+
resources
+
* '''1995''' Vote to fund construction and operation of the new Los Padres dam project is rejected 57% to 43%.
+
 
* '''1996''' ESA listing (threatened) on the red legged frog (Rana aurora draytinii).
 
* '''1996''' ESA listing (threatened) on the red legged frog (Rana aurora draytinii).
 
* '''1997''' ESA listing (threatened) on steelhead trout (Oncorhynchus mykiss).
 
* '''1997''' ESA listing (threatened) on steelhead trout (Oncorhynchus mykiss).
 +
* '''2008''' California Department of Water Resources approved the Carmel River Reroute and San Clemente Dam project.
  
 
== CSUMB Courses Relevant to the Carmel Watershed ==
 
== CSUMB Courses Relevant to the Carmel Watershed ==

Revision as of 21:22, 10 April 2013

Map of the Carmel River Watershed. Image: MPWMD.

Nestled between the Sierra de Salinas and Santa Lucia Mountain Ranges on the Central California Coast, the Carmel River Watershed is composed of countless small tributaries that all drain into the Carmel River, eventually forming the Carmel River Lagoon at Carmel River beach, which periodically breaches into the Pacific Ocean.[1]

Location

The Carmel River Watershed encompasses 255 square miles in Monterey County on the Central Coast of California. The watershed drains into the Carmel River which runs through Carmel Valley and the City of Carmel before reaching the Pacific Ocean. The Santa Lucia mountains create the southern border of the watershed, and the Sierra de Salinas mountains are to the north. [2].

Watershed Components

Main Stem

Carmel River at Schulte Bridge.

The Carmel River main stem is 36 miles long. With its headwaters in the Ventana Wilderness, the upper river is characterized by steep canyons and is relatively undeveloped. The lower 16 miles of river run through moderate to highly developed areas along the alluvial valley before reaching the Carmel River Lagoon [3]. River flow is monitored by the Monterey Peninsula Water Management District at four main stem gaging sites.

Dams

There are two dams on the Carmel River:

Subwatersheds

For ease of study, smaller drainages within the Carmel River Watershed have been identified. These drainages, or subwatersheds, are divided by topographic and hydraulic features [1]. Listed below are links to some of the subwatersheds with prominent issues:

Tributaries

The Monterey Peninsula Water Management District maintains stream gages on several of the tributaries. There are numerous tributaries feeding the Carmel River including but not limited to:

  • Cachagua Creek
  • Pine Creek
  • San Clemente Creek
  • Tularcitos Creek
  • Hitchcock Creek
  • Garzas Creek
  • Robinson Canyon Creek
  • Potrero Creek
  • San Jose Creek

[4]

Lagoon

The Carmel River connects to the Pacific Ocean through the Carmel River Lagoon in winter months when flows are high. In late spring and summer sediment deposits from the river, and offshore sand carried back to the beach by wave activity create a sand berm that closes the river mouth [5]. When the return of winter storms increase lagoon inflow, the lagoon approaches its natural breach point - a level that threatens to flood nearby homes. Currently the County of Monterey addresses the issue by taking emergency action and artificially breaching the lagoon. There are concerns about the effects of artificial breaching on sensitive lagoon species, notably Steelhead Trout [6]. In addition, artificial lagoon breaching may cause a shift in species composition of the lagoon by altering the saline content [1]. Potential lagoon projects address flooding and erosion control, and habitat restoration methods such as the addition of anchored logs to improve steelhead habitat [1].

Physical Characteristics

Hydrology

Precipitation is transported as surface water throughout the watershed via surface water and groundwater pathways. The continuous and complex interaction of groundwater and surface water pathways is determined by several factors, including geology, season, and extraction for human consumption. Annual precipitation, which falls primarily as rain, ranges from 14 inches near the river mouth to 41 inches in the Santa Lucia Mountains.[1]

Surface Water

Surface water in the Carmel River Watershed has several potential outflow pathways that include groudwater withdrawals, transpiration due to riparian vegetation, evaporation from the water surface, and outflow into the ocean. Despite the relatively small size of individual water extraction claims compared to the entire watershed, the sum of all the water use has caused the stream to dry up during the summer months of certain years. This overuse of water supplies pose risks to fish populations.[1]

Groundwater

The Carmel River Watershed is composed of two aquifers: an unconfined alluvial aquifer and a combination of beckrock aquifers located beneath the hills around the watershed. Although the alluvial aquifer has been thoroughly assessed, the bedrock aquifers that provide water resources to large ranches and residences are not well understood. Quantifying the resources available in the in the bedrock aquifers.[1]

Geology

The physical structure of the watershed is primarily dictated by the regional geology, which is composed of igneous, metamorphic and sedimentary rocks. The formations are broken up by several faults with a range of ages and activity. Tectonically, the Carmel Watershed is carved into the Salinian block, which was transported north as part of the Pacific plate. The underlying geology dictates the physical characteristics of the sediment, including the erodibility and landslide potential.[1]

The steep canyons in the headwaters of the Carmel watershed are indicative of recent and sharp incision of the upland streams and tributaries. The high topographic gradient that leads to this incision is due to recent uplift of the Santa Lucia and Sierra de Salinas Ranges. These steep-sided canyons result in a high sediment yield as part of the incision. Additionally, the high gradient and rates of erosion make the terrain vulnerable to slope failure and landslides.[1]

The distribution of valleys and uplands are determined by preferential erosion of less resistive geologic materials. Soils and bedrock that has been crushed in the active Tularcitos fault zone are less resistant to erosion, and therefore create the lowlands in the Carmel River Watershed while the more resistant, intact bedrock composes the uplands and ridges.[1]

Sensitive Species Habitat

Steelhead: The Carmel River supports habitat for the South Central Steelhead Trout Evoluationary Significant Unit and has and supported a run of the federally listed steelhead. Unfortunately, the steelhead population has decreased compared to previous population numbers as well as other populations residing in Northern California streams. Factors such as habitat degredation, introduction of non-native species, and water diversions are likely components that have contributed to the decline. [7]

Red-legged Frogs: The California red-legged frog is present in several areas in the Carmel River Watershed, however, the state of the population is largely unknown. The information regarding the red-legged frog in the watershed is confined to the lagoon and the main stem. [7]

Issues

Watershed issues in the Carmel Watershed are complex and diverse, involving many stakeholders representing many conflicting uses of water.

Water Supply

California American Water (CalAm) extracts water from wells along the river for use by the residents of the Monterey Peninsula, as described here: CalAm Use of Carmel River Groundwater Basin. CalAm is currently making illegal diversions from the Carmel River, according to California State Order 95-10, in order to meet the water demand of the community [8]. Water supply projects incorporating a desalination plant have been proposed by CalAm and local government agencies, as well as private parties [9]. The Monterey Peninsula Water Management District (MPWMD) has initiated Aquifer Storage and Recovery (ASR) projects to capture and store excess winter flows for use during the summer months [10].

Dam Removal

The San Clemente Dam is a 106-foot high concrete dam located just downstream of the convergence of the San Clemente Creek with the Carmel River. Built in 1921, the dam had an initial storage capacity of 1,425 acre-feet, which had been reduced to 70 acre-feet by 2008 due to siltation [11]. Other concerns about the dam include impairment of steelhead runs to upstream spawning grounds, and seismic safety concerns. The California Department of Water Resources (CDWR) Division of the Safety of Dams determined in the early 1990s that the dam could fail in a large earthquake or flood [12]. It has been estimated that an earthquake with a mangitude of up to 7.1 could hit the Tularcitos fault system, with the system's Cachagua fault running beneath the San Clemente reservoir [1].

San Clemente Dam.

Erosion

Sediment movement in the Carmel River Watershed has been impaired by the presence of the Los Padres and San Clemente Dams. Trapping of sediment at the reservoirs has led to incised channels downstream, destabilized banks, and accelerated erosion rates [13]. In addition, grading for urban development in the densely populated lower river valley has created unnaturally steep slopes that further increase the rate of erosion along the river banks. The majority of the watershed is considered vulnerable to erosion [1].

Flooding

Flooding in the Carmel River Watershed has caused significant damage in the past due to the heavily populated urban areas built within the 100-year flood zone [1]. In 1995 there were over 2,720 evacuations, and 800 residences, 68 businesses, 62 roads, and 3 bridges were damaged due to a flood of approximately 16,000 cfs (estimated to be the 65-year flood) [14] [1]. In 1998 a flood of 14,700 cfs flow again caused considerable damage in the Carmel River Watershed [1]. The Monterey County Water Resources Agency provides details of historic flooding in the region dating back to 1911 here.

Projects

Stakeholders

Timeline

Listed below is a brief timeline of water rights and dam operation in the Carmel River Watershed. A more exhaustive timeline is availabe at Carmel River History.

  • 1996 ESA listing (threatened) on the red legged frog (Rana aurora draytinii).
  • 1997 ESA listing (threatened) on steelhead trout (Oncorhynchus mykiss).
  • 2008 California Department of Water Resources approved the Carmel River Reroute and San Clemente Dam project.

CSUMB Courses Relevant to the Carmel Watershed

References

  1. 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14 Physical and Hydrologic Assessment of the Carmel River Watershed California
  2. MPWMD. T. Christensen and E. Geisler. 2009 Riparian Corridor Monitoring Report.
  3. Carmel River Watershed:Water Supply Perspective
  4. Carmel River Basin Principal Streamflow Gaging Stations
  5. Littoral Processes and Breachings at Carmel River Beach
  6. Active Projects in the Carmel River Watershed
  7. 7.0 7.1 MPWMD Environmental and Biological Assessment of Portions of the Carmel River Watershed Monterey County, California
  8. CA State Order 95-10
  9. Monterey County Herald
  10. MPWMD Water Supply Projects
  11. San Clemente Dam Removal Project
  12. San Clemente Dam Removal Project
  13. NOAA and the State Coastal Conservancy - Restoring the Carmel River
  14. MCWRA - Historic Flooding
  15. Carmel River Lagoon Restoration Plan

Links

Disclaimer

This page may contain student work completed as part of assigned coursework. It may not be accurate. It does not necessary reflect the opinion or policy of CSUMB, its staff, or students.