Coastside Capacity WebSite

(The following is an introductory summary of Dennis Coleman's exhaustively researched and very sobering Coastside Capacity Report)

It is well recognized that the Coastside carrying capacity is to some extent limited by (1) a rugged coastline and inland geography; (2) availability and affordability of highway, water, waste treatment and other public infrastructure; and (3) state and federal environmental regulations. The interaction between these local factors and external factors like the overall economy, technological developments, and societal trends, means that City and County land use plans (LCPs) reflect both expressed and implied assumptions about the Coastside carrying capacity. Some of these assumptions are more than 20 years old.

Examples of LCP assumptions that are no longer supported by actual events and trends include:

  • Highway expansion can continue to effectively keep up with peak hour traffic congestion;
  • It will always be possible for the government to raise taxes to subsidize buildout;
  • Enough water will continue to be available and affordable to service buildout;
  • Enough urban services will continue to be available and affordable to service buildout;
  • Land use based on commuter housing and transportation patterns will remain sustainable;
  • Public schools can be fixed with enough State diversion of local taxes in addition to property taxes.

The fact that the accuracy of these and similar assumptions has proven to be highly questionable, is an opportunity to improve LCPs by improving their carrying capacity assumptions based on actual experience. Documentation of such experience has recently been accumulating for traffic, water, schools, services, jobs, substandard lots, public safety, and other indicators of whether the current buildout plan is working as intended.

HMB has recently responded to its experience by initiating revision of its LCP (General Plan). A community visioning document (Public Advisory Committee Report) was produced in mid-1997 and a consultant was contracted in early 1998 to represent that vision in a revised General Plan by late-1999.

Since the adjacent Midcoast experiences the same or similar land use patterns and impacts as HMB, and is deemed by LAFCO to be in HMB's "sphere of influence", the Coastside has a chance to apply new information to improve both County and City LCPs at the same time. After all, results of County and City LCPs have to play out together and make sense. On the ground is where the LCPs, regardless of what they may be separately trying to achieve, will be physically integrated under a unique set of Coastside conditions. The more actual experience is reflected in the LCPs, the more realistic and less controversial the LCPs will be.

This report summarizes recent information from City and County government, district, and other published studies, which indicates that the Coastside carrying capacity is significantly less than that assumed in the current City and County LCPs. The studies indicate that Coastside carrying capacity is particularly challenged with regard to commuter housing. With 7800 new sewer connections available in 1/99, commuter housing could double over the next 20 years according to current LCPs. If the partial (50-60%) build-out achieved to date is already encountering natural, economic, transportation, infrastructure or other key limits, the definition of 100% build-out needs serious reconsideration.


  • Especially during commute hours, SRs 1 and 92 have had high traffic volume to capacity (v/c) ratios since at least 1990, and are projected to have the highest v/c ratios in San Mateo County at LCP buildout. This translates into Caltrans Level of Service index F (prolonged gridlock; average traffic speed for affected highway segment approaches zero; SR 92 "F" segments up to 8 miles long). [Ref. 1: 6/97 CCAG Traffic Modeling Study].
  • Traffic projections based on current LCPs indicate that SRs 1 and 92 are heading towards a higher v/c range, comparable to that experienced on SR 92 during the 1995 Devil's Slide closure of SR 1. These projections already take credit for both growth control and the maximum amount of public spending likely to be available for highway and transit improvements in San Mateo County ($3.2B) between now and 2010. [Ref.1]

The Coastside could be either approaching or experiencing a public health and safety issue relative to traffic, especially during peak commute hours. Even with local EMS-trained people, outside emergency response times for the Coastside are already the highest in the County (37 minutes versus 9 minutes in typical cases).[Ref. 2: 1997 Pacifica COC Meeting, Presentation on Emergency Response Services]

Seen broadly as the range of behavior from annoyance through violence, road rage is now playing a part in 2/3 of fatal traffic accidents. [Ref. 3: 1997 Road Rage articles from CNN and USN]


  • As reported 1/20/98 at a Joint HMB Council/CCWD Board Meeting, about 1000 "priority" (coastal-related, affordable housing, failed wells, etc) water connections remain unsold from CCWD's Phase 1 water supply. Based on a 3/10/98 County Board of Supervisors staff report on a water reallocation appeal, the actual number is about 760. Citizens Utilities (CU; private Montara and Moss Beach water utility) has little or no unused capacity. [Ref. 4: 11/96 MCC presentation on CU's Masterplan Update]
  • If additional (Phase 2) CCWD water supply ever becomes available, it will continue to be limited by nature (e.g. climate, terrain, aquifers), economics (e.g. scarcity, competition, expense) and legal factors (e.e.g. historic ownership, water rights, environmental protection, SFWD contract terms and conditions). [Ref. 5: CCWD 1997 and Phase II Water Supply Reports] CU's forecast supply growth is also limited, corresponding to about 0.7% per year growth in customer demand for water. [Ref. 4] This represents a Coastside residential growth "doubling time" of about 100 years, which is four times longer than the current LCP doubling time of about 24 years.
  • Even approaching the Coastside's carrying capacity relative to water supply, could result in more widespread and/or severe rationing during periodic drought cycles. SFSD reserves the right to unilaterally cut back drought year water supplies by up to 25%, and local supplies are similarly reduced. [Ref. 5] For example, CCWD's maximum "safe yield" (assumed drought condition) water supply is reported to be 541 million gallons for 1998, while the production requirement is estimated to be 862 million gallons. [Ref. 5] LCPs that depend on more water than is reliably available, require current residents to either subsidize expansion or storage facilities for future residents, or risk unnecessary shortfalls and rationing for everybody during the inevitable drought years.
  • CUSD's recent assessment bond study stated that state maximum school fees on new residential development cover only about 1/3 of the actual cost incurred. With a state limit of about $1.90 per square foot of new house (unless otherwise negotiated), that translates into a school district loss of $3.80 per square foot, or $9500 for a 2500 square foot house. [Ref. 6: CUSD Facilities Planning Report] If a higher fee is negotiated, as recently reported in the HMB Review for North Wavecrest Village ($3.80 per square foot school fee), the loss per house is reduced (in this case to about $5000), but rarely eliminated, since state limits are so much lower than reality.
  • Proposition 198 allows the state to divert local government and special district revenue to the Educational Resource Augmentation Fund (ERAF). This fund covers what schools cost to operate beyond what they get from property taxes. The annual ERAF subsidy for the CUSD service area now averages about $125 per residence (~$1M of diverted local taxes, which had been paid for other services like fire protection, water and sewers by ~8000 CUSD residences). [Ref. 7: MCC presentation on ERAF local tax diversion] Since the state legislature has repeatedly not acted to either correct this diversion, or prevent it from increasing, cities and counties are now attempting to put a state constitutional amendment on the ballot. [Ref. 8: 1/98 League of CA Cities presentation on proposed constitutional amendment] In any event, continuing to add residences, which increase demand for schools without contributing to economically sustainable development, is not likely to reduce the ERAF burden.
  • With the exception of local park and recreation services, both City and County provide a similar level of services such as police, public works, social services, etc. Experience shows that property taxes on bedroom communities no longer cover the ongoing expense of such services. [Ref. 9: 1/6/98 HMB Meas. A - Housing Impact Summary] The commuter-oriented residential development emphasized in existing LCPs, may no longer be the most economically viable option.
Jobs/Housing Balance:
  • In recent years, the Coastside population grew more than any other area of the County [Ref. 10: 11/97 SM Times census report], without a corresponding increase in local, high quality jobs. [Ref. 11: 7/97 HMB Baseline Data; Ref. 12: 12/97 HMB Economic Development Report] Recent information from CCAG's housing needs analysis indicates that the Coastside LCPs now calls for at least 4400 more houses than what local job growth can justify (3200 in HMB; 1200 on the Midcoast). [Ref. 13: 11/97 CCAG Housing Needs Analysis] CCAG is developing Congestion Management Program criteria to incent land use planning agencies to reconsider such practices. [Ref. 14: 2/98 CCAG Balanced Growth Program]
Substandard Lots:
  • There has been no definitive planning around the issue of how to manage land use and impacts for thousands of vacant, substandard lots created by Coastside subdivisions more than 90 years ago. Not only are substandard lots uncounted for in the LCP buildout total (~19000 sewer connections worth of buildings), but the number of lots is unknown.
  • The magnitude of this uncertainty can be seen by comparing the number of substandard lots (~5000) manually counted for the Montara Sanitary District (Montara and Moss Beach) [Ref. 15: 8/97 MSD Ltr] with the number of lots (~2000) the County gets from statistical sampling of the entire Midcoast. [Ref. 16: 3/98 County Staff Rpt] There are a few thousand more substandard lots in HMB, but most are in areas zoned Planned Unit Development (PUD). PUD means that an integrated plan is required for development of the whole area, although this could be challenged in court by individual property owners, since the old subdivisions are still legal.
  • Letting market forces and court cases alone determine what happens on such a large, unknown number of substandard lots, introduces so much uncertainty into what the LCPs can accomplish, that the basic LCP assumptions may no longer be applicable.
Airport Safety:
  • The currently under revision HMB Airport Masterplan calls for expansion of usable runway length, taxiways, hangers, parking, special navigational equipment to allow non-visual (bad weather) approaches and landings, and other "landside" facilities to handle projected growth in the annual number of "operations" (takeoffs and landings) from ~38000 in 1996 to ~54000 in 2015. [Ref 17: 1/98 Airport Land Use Plan Update]
  • In recent years, the State has developed and is now recommending a new set of "safety compatibility" criteria, which in effect, recognizes that land use in the vicinity of airports is associated with some public safety risk. [Ref. 17] Previously, 1000 X 2000 foot safety zones on airport-owned land, and various decibel noise limits for the surrounding land were considered in terms of airport impact on that land. [Ref. 17]
  • Based on the location of land within various safety zones, the new recommendations limit concentrations of people and building density and provide open space for emergency situations. Since the safety zones are sized based on runway length, and the HMB Airport has a 5000 foot runway, the zones extend for a mile beyond the sides and ends of the runway. [Ref. 17] This puts much of the urban Midcoast and the northern tip of HMB inside the "Traffic Pattern" and "Inner Turning" zones, including many of the Midcoast substandard lots graphically shown in the previous section.
  • Failure to incorporate the State airport safety compatibility recommendations within the LCP framework could expose the City or County to liability in the event of a future accident involving people and structures on the ground, which were there in violation of such recommendations.